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LESSON 1: SKELETAL SYSTEM Skeletal System The human skeletal system performs a number of key functions in the human body. The key functions of the human skeletal system are:
Support: Our bones provide the rigidity we need to function. Protection: The rigidity of our bones allows them to protect our internal organs from damage for example the rib cage and the skull. Movement: Without the strength of our bones we wouldn‟t be able to move our muscles are anchored to our bones.
Storage: Our bones are a storehouse for fat and certain essential minerals. Blood cell formation: Most of our blood components are made in the bones.
Skeleton Components The skeleton is composed of fibrous and mineralized connective tissues that give it firmness and flexibility. It consists of bone, cartilage, tendons, joints, and ligaments.
Bone - a type of mineralized connective tissue that contains collagen and calcium phosphate, a mineral crystal. Calcium phosphate gives bone its firmness. Bone tissue may be compact or spongy. Bones provide support and protection for body organs.
Cartilage - a form of fibrous connective tissue that is composed of closely packed collagenous fibers in a rubbery gelatinous substance called chondrin. Cartilage provides flexible support for certain structures in adult humans including the nose, trachea, and ears.
Tendon - a fibrous band of connective tissue that is bonded to bone and connects bone to bone.
Ligament - a fibrous band of connective tissue that joins bones and other connective tissues together at joints.
Joint - a site where two or more bones or other skeletal components are joined together. YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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What is a bone made of? A typical bone has an outer layer of hard or compact bone, which is very strong, dense and tough. Inside this is a layer of spongy bone, which is like honeycomb, lighter and slightly flexible. In the middle of some bones is jellylike bone marrow, where new cells are constantly being produced for the blood. Red bone marrow produces new red blood cells for the body. Yellow bone marrow is mainly fat.
Names of Bones The bones that make up your skeleton can be divided into two groups: a.
Axial skeleton consists of the bones in your head, back and chest, while
b. The Appendicular bones are found in the arms and legs, and append, to the body.
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Figure 1. 3. Human skeletal system
Skull The skull consists of 22 separate bones that make up the cranium, the housing for the brain. Twenty-one of those bones are fused together by sutures, nearly rigid fibrous joints. The lower-most bone of the skull is the mandible, or jawbone.
Spine The spine, or vertebral column, is a series of irregularly shaped bones in the back that connects to the skull. At birth, humans have 33 or 34 of these bones. But bones fuse as we age, and the result is 26 separate bones in the spines of adults. YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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Figure 1.5 Backbone or Spine
Rib Cage The rib cage is made up of 12 pairs of bones that encase vital organs in the chest. The bones curve from the back at the vertebral column to the front of the body. The upper seven pairs meet with the sternum, or chest bone. The remaining five pairs are attached to each other via cartilage or do not connect.
Fig . 1.6. Rib cage
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The muscles of the shoulders and arms include the clavicle (collarbone), scapula (shoulderblade), humerus, radius, ulna, and the bones of the wrist and hand. The hip bones are three sets of bones—ilia, ischia, and pubes—that fuse together as we grow older. These form the majority of the pelvis at the base of the spine as well as the socket of the hip joint. The sacrum—five fused bones and at the bottom of the spine—and the coccyx, or tailbone, makes the rest of the bones in the pelvic region. The head of the femur, the largest and longest bone in the body, creates the other half of the hip joint and extends down to form part of the knee. It begins the bones of the leg. The other bones of the leg include the tibia, fibula, and the bones of the ankle and foot. The most common condition that affects bones is fracture, or when a bone endures such a great impact that it breaks. Types of Bones All of the bones of the body can be broken down into five types: long, short, flat, irregular, and sesamoid.
Long. Long bones are longer than they are wide and are the major bones of the limbs. Long bones grow more than the other classes of bone throughout childhood and so are responsible for the bulk of our height as adults. A hollow medullary cavity is found in the center of long bones and serves as a storage area for bone marrow. Examples of long bones include the femur, tibia, fibula, metatarsals, and phalanges.
Short. Short bones are about as long as they are wide and are often cubed or round in shape. The carpal bones of the wrist and the tarsal bones of the foot are examples of short bones.
Flat. Flat bones vary greatly in size and shape, but have the common feature of being very thin in one direction. Because they are thin, flat bones do not have a medullary cavity like the long bones. The frontal, parietal, and occipital bones of the cranium—along with the ribs and hip bones—are all examples of flat bones.
Irregular. Irregular bones have a shape that does not fit the pattern of the long, short, or flat bones. The vertebrae, sacrum, and coccyx of the spine—as well as the sphenoid, ethmoid, and zygomatic bones of the skull—are all irregular bones. Where bones meet Joints are the place where two bones meet. All of your bones, except for one (the hyoid bone in your neck), form a joint with another bone. Joints hold your bones together and allow your rigid skeleton to move. YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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Fixed joints Some of your joints, like those in your skull, are fixed and don't allow any movement. The bones in your skull are held together with fibrous connective tissue. Slightly movable joints Other joints, such as those between the vertebrae in your spine, which are connected to each other by pads of cartilage, can only move a small amount. Synovial joints Most of your joints are 'synovial joints'. They are movable joints containing a lubricating liquid called synovial fluid. Synovial joints are predominant in your limbs where mobility is important. Ligaments help provide their stability and muscles contract to produce movement. The most common synovial joints are listed below:
Ball and socket joints, like your hip and shoulder joints, are the most mobile
type of joint in the human body. They allow you to swing your arms and legs in many different directions.
Ellipsoidal joints, such as the joint at the base of your index finger, allow
bending and extending, rocking from side to side, but rotation is limited.
Gliding joints occur between the surfaces of two flat bones that are held
together by ligaments. Some of the bones in your wrists and ankles move by gliding against each other.
Hinge joints, like in your knee and elbow, enable movement similar to the
opening and closing of a hinged door.
The pivot joint in your neck allows you to turn your head from side to side.
The only saddle joints in your body are in your thumbs. The bones in a saddle
joint can rock back and forth and from side to side, but they have limited rotation. Go Beyond COMMON CONDITIONS THAT AFFECT THE SKELETAL SYSTEM :
Osteoporosis: This is a disease in which the bones become fragile and prone
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Leukemia: This is a cancer of the white blood cells.
Osteopenia, osteitis deformans, and osteomalacia: Similar to osteoporosis,
these are other types of bone loss.
Scoliosis, kyphosis, and lordosis: These are abnormalities of the spinal curve.
ACTIVITY Identify the words being described in each statement. _________________1. It contains the blood vessels and nerves that run through the bones. _________________2. It produces new blood cells for the body. _________________3. It is the only bone in the skull that can move. _________________4. It is a bundle of nerves that carry messages from the brain to the rest of the body. _________________5. It is the strongest and heaviest bone in the body. _________________6. It is where bones connect to each other. _________________7. It is a connective tissue that joins a muscle to a bone. _________________8. It is a smooth and rubbery protein that cushions the inside of a joint.
LESSON 2: MUSCULAR SYSTEM The skeleton is covered by layers of skeletal muscle. Each muscle is attached to two or more bones so that when the muscle contracts (shortens) it produces movement. skeletal muscle makes up about 40 per cent of body weight. As well as producing movement, some muscles remain partially contracted for long periods to maintain the body‟s posture.
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MUSCLE STRUCTURE A skeletal muscle contains many long fibres arranged in bundles called fascicles. Each fibre consists of smaller strands, called myofibrils. These contain yet smaller parts called myofilaments. A muscle contracts when sets of these myofilaments slide past each other in response to nerve signals.
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Front and Back view of the human muscular system
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MUSCLES OF THE BODY There are more than 600 muscles in the body. Their sizes vary from tiny, such as the muscles that move the eyeballs in their sockets, to very large, such as some muscles in the thighs. They are arranged in layers; shown here are the superficial (outer) muscles at the front of the body and, on this side, some of the deeper muscles. SKELETAL MUSCLE Skeletal muscle is also called striated or striped muscle. The stripes, which can be seen clearly when a piece of muscle is viewed under a microscope, are caused by the arrangement of myofilaments in individual muscle fibres. These lead to the appearance of alternating light and dark bands. MOVEMENT Skeletal muscles cross joints and are attached to the bones on either side by tough cords called tendons. They contract, to produce movement, as a result of nerve signals sent from the brain and spinal cord. Although our movements are under our conscious control, the brain can learn patterns of movements so that we can perform certain tasks, such as walking, without thinking. MUSCLE ACTION IN MOVEMENT To straighten the knee, one group of muscles at the front of the thigh contracts, while other muscles at the back of the leg relax. Two groups of muscles such as this are called opposing groups. Contractions of opposing groups have opposite effects, such as knee straightening and bending. There are two fibers in muscle:  
Slow-twitch muscle fibres: Contract slowly, but keep going for a long time. Fast twitch muscle fibres: Contract quickly, but rapidly get tired
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Endurance or speed Slow twitch muscle fibres are good for endurance activities like long distance running or cycling. They can work for a long time without getting tired. Fast twitch muscles are good for rapid movements like jumping to catch a ball or sprinting for the bus. They contract quickly, but get tired fast, as they consume lots of energy. Most of your muscles are made up of a mixture of both slow and fast twitch muscle fibres. But, your soleus muscle in your lower leg and muscles in your back involved in maintaining posture contain mainly slow twitch muscle fibres. And muscles that move your eyes are made up of fast twitch muscle fibres. Dark and white meat Chickens have fast and slow twitch muscle, too. Dark meat, like in chicken legs, is mainly made up of slow twitch fibres. White meat, like in chicken wings and breasts, is largely made up of fast twitch muscle fibres. Chickens use their legs for walking and standing, which they do most of the time. This doesn't use much energy. They use their wings for brief bursts of flight. This requires lots of energy and the muscles involved tire very quickly. Slow twitch and fast twitch muscle fibres make energy in different ways Muscles that contain a lot of slow twitch fibres are red, because they contain lots of blood vessels. Slow twitch muscle fibres rely on a rich supply of oxygenated blood as they use oxygen to produce energy for muscle contraction. Fast twitch muscle fibres don't use oxygen to make energy, so they don't need such a rich blood supply. This is why fast twitch muscles are lighter in colour than muscles that contain a lot of slow twitch muscle fibres. Fast twitch muscle fibres can produce small amounts of energy very quickly whereas slow twitch muscles can produce large amounts of energy slowly. There are three types of muscle tissue:
Skeletal muscle: This type of muscle creates movement in the body. There are more than 600 skeletal muscles, and they makes up about 40 percent of a person‟s weight. When the nervous system signals the muscle to contract, groups of muscles work together to move the skeleton. These signals and movements are nearly involuntary, yet they do require conscious effort. However, humans do not need to concentrate on individual muscles when moving.
Cardiac muscle: Cardiac muscle is involuntary muscle. This type makes up the walls of the heart and creates the steady, rhythmic pulsing that pumps blood through the body from signals from the brain. This muscle type also creates the electrical impulses that produce the heart‟s contractions, but hormones and stimuli YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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from the nervous system can also affect these impulses, such as when your heart rate increases when you‟re scared.
Smooth muscle: Another involuntary muscle type, smooth muscle makes up the walls of hollow organs, respiratory passageways, and blood vessels. It‟s wavelike movements pass things through bodily system, such as food through your stomach or urine through your bladder. Like cardiac muscle, smooth muscle also contracts in response to stimuli and nerve impulses.
LESSON 3: CARING FOR YOUR BONES AND MUSCLES Common Injuries and First-Aid Treatment Fracture
Figure 1. 16. A fracture A fracture is a broken bone, It can be simple or compound. In a simple fracture the bone snaps into two pieces that remain in line with each other. A compound structure is like a simple fracture, but one or both of the broken ends stick out through the skin. A fall a direct blow such as in a motor vehicle crash, or a repetitive force such as in running long distances or ballet dancing can cause fractures. Safety precautions: Wear helmets, knee pads elbow pads and wrist guards when riding bikes or skateboarding.
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Dislocation A blow or a fall can cause dislocation, an injury in which the two bones of a joint become separated. Dislocations may occur in major joints such as your knee or elbow or in smaller joints such as you finger or toe. How to help a person who may have fracture or a dislocation? You should seek medical help at once. While waiting for medical help, do not move the person except if necessary. Do not try to put the broken bones back together or the dislocated bone back in place by yourself. Stop any bleeding by applying pressure to the wound with a clean cloth or sterile bondage. Apply ice wrapped in a towel or a piece of cloth to limit the swelling and help relieve pain.
CRAMP Have you ever felt a pain I your sides, at the bottom of your rib cage, when you run hard over a long distance? It may have been caused by a cramp in your diaphragm. A cramp happens when a muscle suddenly contracts and wll not let go. To help prevent cramps from occurring, warm up before performing an activity.
Sprain and strain A sprain is a stretching or tearing of ligaments, while a strain is a stretching or tearing of muscle or tendon. Sprain often affect the ankle, knee, wrist and thumb, while strains are common in the back, neck and legs. What should you do when you get a sprain or a strain? Rest the part of your body that hurts. Apply an ice pack to help relieve pain and swelling. Wear an elastic compression bandage or splint. Then elevate the injured part higher than your heart. You may use pillows to raise it up. A strain normally heals after a week, but a sprain may take a longer time to heal.
Keeping Your Bones Muscles Strong and Healthy 1. Eat the right kinds of food. Certain nutrients help build bone and muscle strength .protein helps build and repair body cells and tissues.Calcium makes bones and teeth strong.It helps heart and other muscles work and nerve send messages.Meat, fish,poultry,milk,cheese, nuts and dried beans are some of the sources of YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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protein.Milk, cheese,nuts and dried beans are some of the sourcesof protein.Milk, cheese,leafy vegetables, and molasses are rich in calcium. Vitamin D helps the body use calcium and phosphorous, thus helps in keeping bones and teeth strong.Egg yolks,butter,liver, and fish oils are rich in Vitamin D. You can also get Vitamin D from exposure to ealy morning sunlight.
2. Exercise regularly. Regular exercise strengthens your bones and muscles, and enables joints to move freely.Having strong bones and muscles as a child will help prevent osteoporosis and other diseases later in life.
3. Get enough rest and sleep. Getting enough rest and sleep is also important for good health.Sleeping for at least 8 hours a day will give the body the rest that it needs. Activity A. Identify the words being described in each statement. ___________1. It is a broken bone. ___________2. It is an injury in which the two bones of a joint become separate. ___________3.It happens when a muscle suddenly contracts and will not let go. ___________4. It is a stretching or tearing of ligaments. ___________5. It is a stretching or tearing of muscle or tendon.
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LESSON 4: DIGESTIVE SYSTEM
Digestive System Anatomy Mouth Food begins its journey through the digestive system in the mouth, also known as the oral cavity. Inside the mouth are many accessory organs that aid in the digestion of food—the tongue, teeth, and salivary glands. Teeth chop fooD into small pieces, which are moistened by saliva before the tongue and other muscles push the food into the pharynx
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Teeth. The teeth are 32 small, hard organs found along the anterior and lateral edges of the mouth. Each tooth is made of a bone-like substance called dentin and covered in a layer of enamel—the hardest substance in the body. Teeth are living organs and contain blood vessels and nerves under the dentin in a soft region known as the pulp. The teeth are designed for cutting and grinding food into smaller pieces.
Incisors (8 total): The middlemost four teeth on the upper and lower jaws. • Canines (4 total): The pointed teeth just outside the incisors. • Premolars (8 total): Teeth between the canines and molars. • Molars (8 total): Flat teeth in the rear of the mouth, best at grinding food. • Wisdom teeth or third molars (4 total): These teeth erupt at around age 18, but are often surgically removed to prevent displacement of other teeth. The crown of each tooth projects into the mouth. The root of each tooth descends below the gum line, into the jaw.
Tongue. The tongue is located on the inferior portion of the mouth just posterior and medial to the teeth. It is a small organ made up of several pairs of muscles covered in a thin, bumpy, skin-like layer. The outside of the tongue contains many rough papillae for gripping food as it is moved by the tongue‟s muscles. The taste buds on the surface of the tongue detect taste molecules in food and connect to nerves in the tongue to send taste information to the brain. The tongue also helps to push food toward the posterior part of the mouth for swallowing.
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
Salivary Glands. Surrounding the mouth are 3 sets of salivary glands. The salivary glands are accessory organs that produce a watery secretion known as saliva. Saliva helps to moisten food and begins the digestion of carbohydrates. The body also uses saliva to lubricate food as it passes through the mouth, pharynx, and esophagus.
Pharynx The pharynx, or throat, is a funnel-shaped tube connected to the posterior end of the mouth. The pharynx is responsible for the passing of masses of chewed food from the mouth to the esophagus. The pharynx also plays an important role in the respiratory system, as air from the nasal cavity passes through the pharynx on its way to the larynx and eventually the lungs. Because the pharynx serves two different functions, it contains a flap of tissue known as the epiglottis that acts as a switch to route food to the esophagus and air to the larynx.
Esophagus The esophagus is a muscular tube connecting the pharynx to the stomach that is part of the upper gastrointestinal tract. It carries swallowed masses of chewed food along its length. At the inferior end of the esophagus is
a muscular ring called the loweresophageal sphincter or cardiac sphincter. The function of this sphincter is to close of the end of the esophagus and trap food in the stomach. Stomach The stomach is a muscular sac that is located on the left side of the abdominal cavity, just inferior to the diaphragm. In an average person, the stomach is about the size of their two fists placed next to each other. This major organ acts as a storage tank for food so that the body has time to digest large meals properly. The stomach also contains hydrochloric acid and digestive enzymes that continue the digestion of food that began in the mouth.
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Small Intestine The small intestine is a long, thin tube about 1 inch in diameter and about 10 feet long that is part of the lower gastrointestinal tract. It is located just inferior to the stomach and takes up most of the space in the abdominal cavity. The entire small intestine is coiled like a hose and the inside surface is full of many ridges and folds. These folds are used to maximize the digestion of food and absorption of nutrients. By the time food leaves the small intestine, around 90% of all nutrients have been extracted from the food that entered it. Liver and Gallbladder The liver is a roughly triangular accessory organ of the digestive system located to the right of the stomach, just inferior to the diaphragm and superior to the small intestine. The liver weighs about 3 pounds and is the second largest organ in the body. The liver has many different functions in the body, but the main function of the liver in digestion is the production of bile and its secretion into the small intestine. The gallbladder is a small, pear-shaped organ located just posterior to the liver. The gallbladder is used to store and recycle excess bile from the small intestine so that it can be reused for the digestion of subsequent meals. Pancreas The pancreas is a large gland located just inferior and posterior to the stomach. It is about 6 inches long and shaped like short, lumpy snake with its “head” connected to the duodenum and its “tail” pointing to the left wall of the abdominal cavity. The pancreas secretes digestive enzymes into the small intestine to complete the chemical digestion of foods.
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Large Intestine The large intestine is a long, thick tube about 2 ½ inches in diameter and about 5 feet long. It is located just inferior to the stomach and wraps around the superior and lateral border of the small intestine. The large intestine absorbs water and contains many symbiotic bacteria that aid in the breaking down of wastes to extract some small amounts of nutrients. Feces in the large intestine exit the body through the anal canal.
The digestive system is responsible for taking whole foods and turning them into energy and nutrients to allow the body to function, grow, and repair itself. The six primary processes of the digestive system include: 1. 2. 3. 4. 5. 6.
Ingestion of food Secretion of fluids and digestive enzymes Mixing and movement of food and wastes through the body Digestion of food into smaller pieces Absorption of nutrients Excretion of wastes
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Ingestion The first function of the digestive system is ingestion, or the intake of food. The mouth is responsible for this function, as it is the orifice through which all food enters the body. The mouth and stomach are also responsible for the storage of food as it is waiting to be digested. This storage capacity allows the body to eat only a few times each day and to ingest more food than it can process at one time. Secretion In the course of a day, the digestive system secretes around 7 liters of fluids. These fluids include saliva, mucus, hydrochloric acid, enzymes, and bile. Saliva moistens dry food and contains salivary amylase, a digestive enzyme that begins the digestion of carbohydrates. Mucus serves as a protective barrier and lubricant inside of the GI tract. Hydrochloric acid helps to digest food chemically and protects the body by killing bacteria present in our food. Enzymes are like tiny biochemical machines that disassemble large macromolecules like proteins, carbohydrates, and lipids into their smaller components. Finally, bile is used to emulsify large masses of lipids into tiny globules for easy digestion. Mixing and Movement The digestive system uses 3 main processes to move and mix food:
Swallowing. Swallowing is the process of using smooth and skeletal muscles in the mouth, tongue, and pharynx to push food out of the mouth, through the pharynx, and into the esophagus.
Peristalsis. Peristalsis is a muscular wave that travels the length of the GI tract, moving partially digested food a short distance down the tract. It takes many waves of peristalsis for food to travel from the esophagus, through the stomach andintestines, and reach the end of the GI tract.
Segmentation. Segmentation occurs only in the small intestine as short segments of intestine contract like hands squeezing a toothpaste tube. Segmentation helps to increase the absorption of nutrients by mixing food and increasing its contact with the walls of the intestine. Digestion Digestion is the process of turning large pieces of food into its component chemicals. Mechanical digestion is the physical breakdown of large pieces of food into smaller pieces. This mode of digestion begins with the chewing of food by the teeth and is continued through the muscular mixing of food by the stomach and intestines. Bile produced by the liver is also used to mechanically break fats into smaller globules. YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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While food is being mechanically digested it is also being chemically digested as larger and more complex molecules are being broken down into smaller molecules that are easier to absorb. Chemical digestion begins in the mouth with salivary amylase in saliva splitting complex carbohydrates into simple carbohydrates. The enzymes and acid in the stomach continue chemical digestion, but the bulk of chemical digestion takes place in the small intestine thanks to the action of the pancreas. The pancreas secretes an incredibly strong digestive cocktail known as pancreatic juice, which is capable of digesting lipids, carbohydrates, proteins and nucleic acids. By the time food has left the duodenum, it has been reduced to its chemical building blocks— fatty acids, amino acids, monosaccharides, and nucleotides. Absorption Once food has been reduced to its building blocks, it is ready for the body to absorb. Absorption begins in the stomach with simple molecules like water and alcohol being absorbed directly into the bloodstream. Most absorption takes place in the walls of the small intestine, which are densely folded to maximize the surface area in contact with digested food. Small blood and lymphatic vessels in the intestinal wall pick up the molecules and carry them to the rest of the body. The large intestine is also involved in the absorption of water and vitamins B and K before feces leave the body.
Excretion The final function of the digestive system is the excretion of waste in a process known as defecation. Defecation removes indigestible substances from the body so that they do not accumulate inside the gut. The timing of defecation is controlled voluntarily by the conscious part of the brain, but must be accomplished on a regular basis to prevent a backup of indigestible materials.
Activity Label the organs in this illustration
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A. Arrange in chronological order the stage that takes place during the process of digestion. Number the items 1 to 5.
_______1. Food is temporarily stored in the stomach. _______2. Nutrients are absorbed in the small intestine. _______3. Food s cut into pieces, moistened and chewed . _______4. The large intestine gets waste product ready for disposal. _______5. Food passes through the esophagus.
B. Underline the words inside the parentheses that will complete the sentence correctly. YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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1. Digestion begins in the (mouth, stomach). 2. The muscular movement in which alternating waves of contraction and relaxation caused food to be squeezed along the digestive tract is called ( bolus, peristalsis). 3. In the small intestine, a yellowish fluid called (bile,villi) flows to help digest foods. 4. In the stomach food is turned into (chyme,enzyme) with the help of digestive juices called acids. 5. The solid waste will be expelled out of the body through the (anus, feces).
LESSON 5: CARING FOR THE DIGESTIVE SYSTEM Nutrients and Your Body An essential nutrient is a nutrient that the body cannot synthesize on its own -- or not to an adequate amount -- and must be provided by the diet. These nutrients are necessary for the body to function properly. The six essential nutrients include carbohydrates, protein, fat, vitamins, minerals and water. Carbohydrates
Fig. 2.8 sources of carbohydrates Carbohydrates are the main energy source for the brain. Without carbohydrates, the body could not function properly. Sources include fruits, breads and grains, starchy vegetables and sugars. Make at least half of the grains you consume whole grains. Whole grains and fruit are full of fiber, which reduces the risk of coronary heart disease and helps maintain normal blood glucose levels. YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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The different kinds of carbohydrates include starch ,sugar and fiber: o
Sugar
Some of the most familiar sugars include glucose, fructose, sucrose and lactose. Glucose is better known as blood sugar, but like fructose and sucrose it's also a natural sugar found in fruits and vegetables. Lactose is the natural sugar in milk. Sugars gain rapid access to your bloodstream because they have so few sugar molecules to digest. When you obtain natural sugar from whole foods, you gain the energy boost together with vital nutrients. Added sugars, in contrast, contribute calories for energy but don't have other redeeming qualities. They lack nutrients, cause unhealthy spikes in blood sugar and promote weight gain, notes the American Heart Association. o
Starch
Starch is made from chains of simpler sugars that are broken down during digestion to give you energy. Foods derived from plants, like rice, bread, corn, potatoes, cereals and pasta are good sources of starch o
Fiber
When you consume fiber, most of it goes through your digestive tract without being digested, but some types are fermented in the large intestine. Fiber-rich foods, such as beans, fruits, vegetables and whole grains, contain different proportions of the two types of fiber: soluble and insoluble. Soluble fiber keeps your blood sugar steady by slowing down the absorption of carbs into your system. It also interferes with the absorption of dietary fat and cholesterol, which can help lower your blood cholesterol level. Insoluble fiber prevents constipation by keeping digestive wastes moving through your intestines. Women should consume 25 grams of fiber daily, while men need to get 38 grams each day, according to the Institute of Medicine. Protein Protein is the major structural component of cells and is responsible for the building and repair of body tissues. Protein is broken down into amino acids, which are building blocks of protein. Nine of the 20 amino acids, known as essential amino acids, must be provided in the diet as they cannot be synthesized in the body. Ten to 35 percent of your daily calories should come from lean protein sources such as lowfat meat, dairy, beans or eggs.
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Figure. 2.9 sources of protein Fat Fat is energy source that when consumed, increases the absorption of fatsoluble vitamins including vitamins A, D, E and K. Twenty to 35 percent of your daily intake should come from fat. Choose healthy options such as omega-3-rich foods like fish, walnuts and vegetable-based oils. Omega-3s help with development and growth. Limit intake of saturated fats such as high-fat meats and full-fat dairy. Other smart choices include nuts, seeds and avocado.
Figure 2.10.sources of fats
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Vitamins Vitamins are regarded as micronutrient because your body requires them in small amounts only.Some vitamins, their uses and their food sources are listed in Table 2.1 Table 2.1 Some vitamins your body needs Vitamin Some Uses in Your Body Keeps skin smooth and the A linings of mouth, nose, throat, lungs, and intestines healthy; forms the part of the eye which helps to see in dim light; helps prevent certain types of cancer B1 Works with other B vitamins to (Thiamine) help your body use the energy it gets from food; improves appetite; helps keep the nervous system healthy
Some Sources Dark orange and green vegetables and fruits like carrot, squash, sweet potato, broccoli, red and green peppers; egg yolks; milk; cheese; liver Whole grain foods as brown rice, grits and whole-wheat bread; baked beans, black beans, black-eyed peas and peanuts; nuts, seeds and other vegetables and fruits; lean pork; organ meats such as liver, heart and kidney
B2 (Riboflavin) Works with other B vitamins to help your body use the energy you get from food; helps the body to use protein in food to build new cells and tissues
Animal products like milk, cheese, yogurt, beef and poultry; some green vegetables such as broccoli, turnip greens and spinach
Works with other B vitamins to help your body use the energy you get from food; helps the body to use protein in food to build new cells and tissues Helps the body to use protein in food to build new cells and issues
Most kinds of meat, poultry, fish
B3 (Niacin)
B6 (Pyridoxine)
B12 (Cobalamin) C
Keeps blood healthy
K
Helps blood to clot properly
Helps form a cement-like material between your cells; helps to heal cuts, wounds and burns; helps in preventing certain types of cancer
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Animal products like pork, liver, kidney, poultry, eggs and fish; whole grain foods (brown-rice, whole-wheat bread and oatmeal? Eggs, milk, cheese Many fresh fruits like orange, lemon, lime, grapefruit, cantaloupe, mango papaya and their juices; vegetables such as bean sprouts, green pepper and broccoli Green leafy vegetables Page 27
Minerals Like vitamins, minerals are regarded as micronutrients. Some of the minerals, their uses and their food sources are listed in Table 2.2
Mineral Calcium
Some uses in your body
Some sources
Helps build strong bones and teeth; helps your heart, nerves and muscles
Milk and foods made from milk, like yogurt and pudding; green leafy vegetables; tofu; canned fish with bones
Helps build strong bones and teeth; function in cell activities
Whole grains, beans, peas, milk, meat, liver, eggs, fish
Phosphorous
Iodine
Seafood, iodized salt Helps the thyroid gland to control the bodyâ€&#x;s use of energy
Iron Helps blood carry oxygen from your lungs to your muscles, and organs
Fish; eggs, beef, pork, chicken turkey, clams and oysters; soybeans, lentils and kidney beans; spinach and other green leafy vegetables; flour
Helps muscles contract; helps keep nerves calm; needed for energy release
Raw, green leafy vegetables; whole grains, nuts
Needed for growth
Oysters, meat, liver, eggs, raw and natural foods
Magnesium
Zinc
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Water Do you know that you can survive longer without food than you can without water? Water is essential for life itself. It makes up two-thirds of your body, 80% of your body, 80% of your blood, and 30 percent of your bones. Your body uses water in many body processes such as breaking down food, carrying wastes out of the body, and controlling body temperature. The water you lose when you breathe, sweat, urinate and defecate must be replaces. Drinking six to eight glasses of water is recommended including water in soup, milk and fruit juices as well as from vegetables and fruits. Water helps to maintain homeostasis in the body and transports nutrients to cells. Water also assists in removing waste products from the body. All beverages and high-moisture foods such as soup and watermelon contain water and count towards your daily water requirement. Adults should consume 25 to 35 millilitres of fluids per kilogram body weight or 2 to 3 liters per day.
The Food Pyramid The food and Nutrition Research Institute FNRI) of the Department of Science and Technology(DOST) gives the food pyramid in Figure 2.11 as a guide in planning a balanced diet.
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Figure. 2.11 Food pyramid Some Common Digestive Disorders A digestive disorders disrupts the supply of nutrients in the body. Do you know some of the most common digestive disorders? What are their symptoms and how can they be prevented or treated?
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Constipation Constipation is a difficult or infrequent passing of stool. To prevent or relieve constipation, eat high-fiber foods, drink plenty of water and other liquids, and exercise regularly. Chewing your food regularly also helps prevent constipation. Recall that digestion begins in the mouth. Chewing your food well helps to break down food and to better absorb nutrients. Some medicines can cause constipation, so ask your doctor if you are taking any medicine and experiencing constipation. Diarrhea Diarrhea, in contrast with constipation, is the passing of loose, watery stool. A person with diarrhea may pass stool more than three times a day. A few of the causes of diarrhea are bacterial or viral infections, and intake of food that has a component the person cannot digest. Diarrhea usually goes away on its own, but a prolonged case may cause dehydration. Dehydration is the loss of too much fluid and electrolytes of the body. It are particularly dangerous in children and in older people so it must be treated promptly. Diarrhea can be prevented by taking in only clean food and water, washing your hands before touching food and practicing personal hygiene. Peptic Ulcer A peptic ulcer is a ore in the lining of your stomach, the first part of your small intestine called duodenum, or your esophagus. It may be caused by the bacteria H. pylori, or frequent and prolonged intake of pain relievers. The symptoms include abdominal pain that comes and goes for several days or weeks, bloating .burping and vomiting. Peptic ulcers can be cured with the right medicines prescribed by a doctor upon consultation. To prevent peptic ulcers caused by H. pylori infection , washes your hands before eating and after using the comfort room. Moreover, drink water only from a clean, safe source. Activity A. Give five examples of food rich in the given nutrients. 1. carbohydrates________________________________________________________ _________________________________________________________________ 2. proteins_____________________________________________________________ _________________________________________________________________ 3. fats________________________________________________________________ _________________________________________________________________ YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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4. vitamins____________________________________________________________ _________________________________________________________________ 5. minerals____________________________________________________________ _________________________________________________________________
B. Write T if the statement is true.Write F if it is false. ______1. All parts of food can be digested. ______2. Wter helps control your body temperature. ______3.The amount of food that each person needs to eat varies. _____4. The B vitamins help your body use the energy you get from food. _____5.Phosphous helps make bones and teeth strong. _____6. Starch tastes sweet.
Go Beyond Find out the recommended energy and nutrient intakes (RENI) for children your age. Look IN a book in your library or search the internet for a list of nutrients contained in different foods. Write down all the foods you get in one day and check if you are getting enough of each nutrient. A sample is written for you..
Meal
Food
Amount
Nutrients
Breakfast
rice
1 cup
carbohydrates
Lunch
Dinner
Snacks YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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http://healthyeating.sfgate.com/6-essential-nutrients-functions-4877.html
LESSON 6: REPRODUCTION OF ANIMALS
Reproduction is the process by which animals produce a young of their own kind or offspring. Vertebrates, are animals that have backbones. Mammals, birds, amphibians, reptiles and fish are the main groups of vertebrates. Invertebrates are those animals that do not have backbones. Mollusks, crustaceans and insects are the few groups of invertebrates. Animals may also be grouped by how they reproduce. Live-breeders are animals that give birth to their young. Mammals are animals that have mammary glands. Most mammals are live-breeders. Their mammary glands produce milk which their babies feed on. Egg-layers are those which lay eggs that hatch into their young. All birds, most fishes, early all amphibians, most reptiles and most invertebrates are egg-layers. The number of eggs that each type of animals has varies. Activity 1 List at least ten parent animals and their young. Then put a check under the correct column. Animal Parent Baby animal Born Alive Hatched from eggs Dog
puppy
chicken
Chick
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What Is Reproduction? In a nutshell, reproduction is the creation of a new individual or individuals from previously existing individuals. In animals, this can occur in two primary ways: through asexual reproduction and through sexual reproduction.
1. Sexual reproduction , the process of forming a new individual from two parents. Animals often have gonads , organs that produce eggs or sperm. The male gonads are the testes , and the female gonads are the ovaries . Testes produce sperm; ovaries produce eggs. Sperm and egg, the two sex cells, are known as gametes , and can combine two different ways, both of which combine the genetic material from the two parents.
Fish and other aquatic animals release their gametes in the water, which is called external fertilization ( Figure below ). These gametes will combine by chance.
Animals that live on land reproduce by internal fertilization . Typically males have a penis that deposits sperm into the vagina of the female. Birds do not have penises, but they do have a chamber called the cloaca that they place close to another bird‟s cloaca to deposit sperm.
2.
Asexual Reproduction
In asexual reproduction, one individual produces offspring that are genetically identical to itself. These offspring are produced by mitosis. There are many invertebrates, including sea stars and sea anemones for example, that produce by asexual reproduction. Common forms of asexual reproduction include: Budding
In this form of asexual reproduction, an offspring grows out of the body of the parent.
Hydras exhibit this type of reproduction.
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Gemmules (Internal Buds)
In this form of asexual reproduction, a parent releases a specialized mass of cells that can develop into offspring.
Sponges exhibit this type of reproduction.
Fragmentation
In this type of reproduction, the body of the parent breaks into distinct pieces, each of which can produce an offspring.
Planarians exhibit this type of reproduction.
Regeneration
In regeneration, if a piece of a parent is detached, it can grow and develop into a completely new individual.
Echinoderms exhibit this type of reproduction.
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Parthenogenesis 
This type of reproduction involves the development of an egg that has not been fertilized into an individual. 
Animals like most kinds of wasps, bees, and ants that have no sex chromosomes reproduce by this process. Some reptiles and fish are also capable of reproducing in this manner.
Activity: Identify what is being described in each sentence. ______________1.It is the process where an animal produce a young of their kind. ______________2. The type of reproduction that only involves one parent. ______________3. Type of asexual reproduction wherein if a piece of parent is detached,it can grow and develop into a new individual. ______________4.A kind of fertilization which happens inside the body of the organism. ______________5.The type of reproduction that involves two parent ,a male and a female sex cells. ______________6. In this type of reproduction, the body of the parent breaks into distinct pieces, and each of which can produce an offspring. ______________7. Hydra, is an example of an offspring that grows out of the body of the parent undergo this type of fertilization. ______________8.The male sex cells. ______________9.The female sex cells. ______________10. The union of male and female sex cells. YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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LESSON 7: LIFE CYCLES Like human beings .animals change as they grow. Similarly they have different stages of growth and development from birth to adulthood. These stages makeup their life cycle.
The Life Cycle of a Dog A mother dog carries its young inside its body for about nine weeks. It can give birth to up to eight puppies at a time. Each puppy looks a lot like its parebnts from the moment it is born. However, a puppy cannot see or hear. It uses its sense of smell to find its mother so it can feed on milk. The puppy will start seeing things when it is about 10 days old. It will start hearing sounds a few days later. A puppy seeps and feeds on milk a lot. At about three months old, it is ready to leave its mother. As the young dog grows, it will eat other kinds of food such as meat. When it is fully grown, it can have its own puppies.
Life Cycle of a Chicken A chicken goes through three stages in its life cycle: egg, chick and adult chicken. A hen usually lay eggs one egg a day. Only fertilized eggs will hatch into chicks. Chicken eggs, like other birds, are protected by a hard shell. A hen keeps her egg warm by sitting on them. This is called brooding. Each egg has to be kept warm all over so that the chick inside will grow. Inside the egg, the chick gets food from the yellow yolk and the white of the egg called albumen.
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After about three weeks, the egg is ready to hatch. The chick chips the shell with the sharp point I its beak called an egg tooth. It pushes the shell apart with its body. When the chick comes out, its feathers are wet. The feathers become fluffy once they dry.
In just a few months, the chick grows into an adult chicken. A hen stats laying eggs at six months old. When it mates, anew cycle begins.
Figure 3.7 Stages in the life of a chicken Metamorphosis Some animals such as frogs an butterflies undergo many changes during their life span. A complete or marked change in the form of an animal is called metamorphosis. The word metamorphosis comes from the greek words meta, meaning „‟‟to change,‟‟ and morphe , meaning „‟form‟‟ Animals that have four stages of development undergo complete metamorphosis. They start life as eggs. become larvae, then pupae, before they became adult animals. Bettles, wasps, bees, ants, flies, moths and butterflies undergo complete metamorphosis Animals that have only three stages of development undergo incomplete metamorphosis. After they hatch from eggs, the young look very similar to their parents. Life Cycle of a frog The Egg Frogs lay their eggs in water or wet places. A floating clump of eggs is called frog spawn. YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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The large and slippery mass of eggs is too big to be eaten. This is nature's way of protecting them. But, the smaller clumps of eggs will be eaten by the creatures living near or in the pond. The egg begins as a single cell. Several thousand are sometimes laid at once. It becomes surrounded by a jellylike covering, which protects the egg. The female may or may not stay with the eggs to take care of the young after she has laid them. The egg slowly develops. But, only a few develop into adults. Ducks, fish, insects, and other water creatures eat the eggs. The mass of cells in the egg come to form an embryo. Organs and gills begin to form, and in the meantime, the embryo lives off of its internal yolk. This supplies it with nutrients for 21 days. Then .. The Tadpole
After its 21 day development period, the embryo leaves its jelly shell, and attaches itself to a weed in the water. This quickly becomes a tadpole, a baby frog. The tadpoles grow until they are big enough to break free into the water. This can take from 3 days to 3 weeks, depending on what kind of frog they will become. They eat very small plants that stick to larger plants in the water. These tiny plants are called algae. The tadpole has a long tail, and lives in the water. It is extremely vulnerable, and must rely on its camouflage to protect it. The tadpole has a long tail, and lives in the water. It is extremely vulnerable, and must rely on its camouflage to protect it. The tadpoles also face danger by being eaten by other water animals. Sometimes the pond dries up. As a result the tadpoles die.
The Tadpole Begins To Change After about five weeks, the tadpole begins to change. It starts to grow hind legs, which are soon followed with forelegs. Behind their heads bulges appear where their front legs are growing. Their tails become smaller. Lungs begin to develop, preparing the frog for its life on land. Now and then, they wiggle to the surface to breathe in air. The tail becomes larger and makes it now possible for the tadpole to swim around and catch food. They eat plants and decaying animal matter. Some tadpoles eat frogs eggs and other tadpoles.
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Figure 3.8 Stages in the life of a frog Over time, the tadpole becomes even more froglike. They have shed their skin and lips. Its mouth widens, and it loses its horny jaws. The tail becomes much smaller, and the legs grow. The lungs are almost functioning at this point. The Frog Eleven weeks after the egg was laid, a fully developed frog with lungs, legs, and no tail emerges from the water. This frog will live mostly on land, with occasional swims. The tiny frogs begin to eat insects and worms. Eventually, it will find a mate. The way this is done varies depending on the species. The female lays the eggs, the male fertilizes them, and the whole process begins again.
Life Cycle of a Butterfly Butterflies go through a life cycle. A butterfly has four stages in its life cycle. Each stage is different. Each stage also has a different goal. A butterfly becoming an adult is called metamorphosis. The life cycle process can take a month to year. It depends on the type of butterfly. Stage 1: Eggs In the first stage a girl butterfly lays eggs. A butterfly first starts out as an egg. A girl butterfly lays the eggs on a leaf. She lays the eggs really close together. The eggs are really small and round. About five days after the eggs are laid. A tiny worm-like creature will hatch from the egg.
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Stage 2: Caterpillar (Larve) The second stage is the caterpillar. A caterpillar is sometimes called larvae. A caterpillar is a long creature. It looks like a worm. Most caterpillars have a cool pattern. This pattern has stripes or patches. The caterpillar is hungry once it has hatched. It starts to eat leaves and flowers. It eats these all the time. It first eats the leaf that it was born on. This is the eating and growing stage.
A caterpillar grows really fast. This is because they eat a lot. A caterpillar is really small when it is born. It starts to grow fast. This is because it eats all the time. It grows so fast that it becomes too big for its skin. So the caterpillar has to shed its old skin. It then gets new skin. Caterpillars shed their skin four or more times while they are growing. A caterpillar shedding its outgrown skin is called molting.
Caterpillars do not stay in this stage very long. While they are in this stage, all they do is eat.
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Stage three is the chrysalis. This is when the caterpillar is done growing. The caterpillar makes a chrysalis. Another name for a chrysalis is a pupa. It is mostly brown or green. It is the same color as the things around it. Things like the trees, leaves, or branches. This is so that other animals cannot see it. This protects them. This keeps them from getting hurt.
This is the resting stage. It also is the changing stage. The caterpillar starts to changes. It starts to turn into a butterfly. It starts to look different. Its shape starts to change. It changes quickly. It then turns into a butterfly. All this happens in the chrysalis. This does not take a long time.
Stage 4: Butterly (Adult) (Imago) In stage four, the chrysalis opens. Soon a butterfly comes out. A butterfly is sometimes called an imago. It is also called an adult. Butterflies are very colorful. When the butterfly first comes out its wings are damp. The wings are also soft. The wings are folded against its body. The butterfly is also very tired. So the butterfly rests. Once the butterfly has rested, it will be ready to start flying. It will start to pump blood into its wings. This is to get them working and flapping. After it does this, it can now learn to fly. Butterflies cannot fly good at first. They need a lot of practice. It does not take long for them to learn. They learn fast. When it can fly, it will go look for food. The butterfly will also go look for a mate. It will soon find a mate. It will then lay eggs. The lifecycle will start all over again.
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Activity A. Sequence the given stages of growth in the life of a frog.Write numbers 1 to 6 on the space provided. B. ____Eggs are hatched into tadpoles. ____ An adult frog lays a clump of eggs in the water. ____its gills disappear. ____ It begins its life on land. ____its hind legs begin to grow. ____ its tail starts to shrink. B. Write each insect under the correct column. Moth
mosquito
bettle
Dragonfly
louse
cockroach
Complete metamorphosis
YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
grasshopper bee ant
wasp
Incomplete metamorphosis
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LESSON 8: USEFUL ANIMALS Animals are very useful to people. Some animals are raised to be sources of food and materials. Other animals are helpful at work. people keep some animals as pets. In farm poultry such as chickens, ducks and quails are raised for meat and eggs. Cows and goats are raised for meat and milk. Pigs are raised for their meat. There are also fish farms where people breed fish and prawns. But animals that are sources of food are not only found in farms. Fish and other seafoods , for instance, are caught from open seas.
Figure 3.10. Food items from animals Some animals are also sources of clothing materials. One example is a leather shoes. Leathers are processed animal skin of cows, carabaos, crocodiles or snakes. Aside from shoes, they are also made into belts, watch straps, wallets, bags and jackets.
Figure 3.11.Products made from processed animal skin Sometimes jackets and coats are lined with fur or animal hair. But animal welfare groups are against raising or hunting animals such as minks, foxes and bears for their fur. Other clothing materials that are sourced from animals are fleece and silk. Fleece comes from the wool of sheep. Aside from clothes, it is usually made into socks, gloves, rugs and blankets. Silk on the other hand comes YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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from the cocoons of silkworms. Because it is soft and smooth, silk is a fine material for clothing and beddings.
Figure3.12 Clothing materials and accessories sourced from animals. Materials from animals can also be used in making accessories and decorations. Pearls from oysters are made into earrings and necklaces. Oyster shells can be made into window panes and lamp shades. Some animals are useful in doing work. They are sometimes called beasts of burden. The carabao is one of these animals. It is not only used in plowing the field but also in pulling carts to transport people and things. Other animals that are used for transportation are cows, horses, elephants, dogs and camels.
Figure 3.13. Animal used for work Some animals are trained to entertain people. Dogs can be taught to fetch a Frisbee, shake hands, roll over and bark a certain number of times. Lions are trained to jump through rings of fire: seals to balance balls in their noses; and dolphins to jump in unison and perform other acts. Just as animal welfare groups are against the use of animals in entertainment.
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Figure 3.14. Animal used in entertainment Some animals are kept as pets. Among the most common pets are dogs, cats, fishes and birds. Pets give their owners joy.
Activity 1. Draw a line to match each animal in Column A with an item in Column B. A
B
1.
2.
3.
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4.
5.
LESSON 9: HARMFUL ANIMALS Animals that bring harm to people or to their concerns such as their crops or pets are considered pests. They usually cause diseases or spread the germs that can cause diseases. Birds In general birds are not considered harmful animals. Some kinds of birds are now even protected because they are endangered. However, some birds are considered pests because of their droppings, their associated pests, and their potential to spread diseases. Droppings can cause damage to buildings and monuments, clog gutters and pipes and serve as medium for breeding flies. Other pests such as fleas, lice, ticks and mites also live in their nests and on their feathers. Some birds considered as pests include pigeons, house sparrows, and crows.
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An infectious disease of birds that can be transmitted to humans is Avian influenza or bird flu. Early symptoms include high fever, diarrhea, vomiting, abdominal pain, chest pain and bleeding from the nose and gums. Although still considered a rare disease to humans. Avian influenza is closely watched and studied because of its severity. Mosquitoes
Mosquitoes are among the worldâ€&#x;s harmful animals. Thought to have contributed to 50% of all natural human deaths since the beginning of recorded history, mosquitoes pass on diseases when they feed on human blood. Two of these diseases are malaria and dengue. Malaria is a life-threatening disease characterized by recurring chills and fever. It is caused by parasites that are spread to people through the bites of infected Anopheles mosquitoes. Malaria-carrying mosquitoes usually bite at night. They breed in shallow collections of freshwater like puddles and rice fields. More that 85% of world malaria deaths are in Africa, mostly in young children. This is because the Anopheles mosquitoes in Africa have a long life span and a strong human-biting habit, and children have lower immunity. Malaria however can be prevented and cured. Another mosquito-borne disease is dengue, an infection caused by a virus transmitted to humans through the bites of infected Aedes mosquitoes. Dengue fever is characterized by fever with rash in infants and young children and by high fever, severe headache, pain behind the eyes, muscle and joint pains, and rash in older children and adults. Mosquito populations rise in areas where residents commonly store in open containers and where solid waste disposal services are inadequate. Covering water containers tightly and properly disposing of solid wastes are two things that
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people can do to help control mosquito population and prevent dengue from spreading. Cockroaches
Cockroaches can live anywhere as long as there is water, but they thrive in warm, dark and wet places. They are harmful mainly because they can contaminate food. They shed off skin which can trigger allergic reactions in people. They also secrete an unpleasant odor. To prevent cockroaches from breeding in your house, keep all storage areas clean and dry.
Flies
Flies breed in garbage piles and other dirty places .They feed on decaying matter. They suck up only liquids, but they can turn solid decaying matter in a liquid with their spit or vomit. They are known to carry many kind of germs that can cause diseases such as dysentery and typhoid. Dysentery is a chronic disease that a affect a person‟s large intestine. It is characterized by severe diarrhea and stomach cramps. Typhoid is a type of fever with symptoms that include a high body temperature (39˚C to 40˚C), weakness, stomach pain, headache and loss of appetite. Keeping the surroundings clean, disposing of wastes properly, and installing screens on doors and windows can keep flies away from your area. Rats
Rats are known to eat and chew anything. They are considered scavengers. They eat peoples stored foods. They may even chew on wires, which can cause fire to start. They carry disease-causing germs. Water contaminated with YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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their urine can cause leptospirosis, a rare and severe infection. Symptoms of leptospirosis, include severe headache, redness in „the eyes, muscle pains, fatigue, nausea, and fever of 39˚C .To keep rats away from your house, maintain cleanliness. Moreover, close up the holes and cracks through which rats can come into your house. First Aid for Insect Bites and Stings Your reaction to a specific insect bites or sting may be different from another person‟s reaction. Most reactions are mild, such a itching and swelling. To reduce any pain and swelling, you may apply a cold pack or cloth filled with ice. You may also apply hydrocortisone cream or baking soda paste, a mixture of three parts baking soda dissolved in one part water. Severe allergic reactions would require medical treatment. Symptoms include difficulty in breathing, swelling of the lips or throat, faintness, dizziness, confusion, rapid heartbeat, nausea, cramps and vomiting. Have the person who has been bitten or stung lie still with feet higher than the head .If there is vomiting, turn the person to his or her side to prevent choking. Loosen tight clothing and cover the person with a blanket. First Aid for Animal Bites Animals bites when they feel threatened or hurt. Pets such as dogs and can cause most animal bites. Because they might carry rabies, a virus that can cause a fatal disease, they should get antirabies shots. If an immunized animal bites you or someone you are with, and the bite barely breaks the skin, wash the area with soap and water. Apply antibiotic cream and bandage the wound. If the bite tears the skin and causes bleeding, or there is a risk of rabies, you have to see a doctor immediately. Stop the bleeding by applying pressure on the wound with a clean dry cloth. Activity 1 Match the animals in Column A with the diseases they spread in Column B. A _____1.Aedes mosquitos _____2. Anopheles mosquitoes _____3. Birds _____4. Flies _____5. Rats
YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
B a. Avian flu b. dengue c. dysentery d. leptospirosis e. malaria f. yellow fever
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LESSON 10: FLOWERING PLANTS
How Plants are Grouped There are many ways to grouped plants. Plants can be grouped as trees, shrubs, grasses, and vines. Trees are woody plants that live for a very long time. Shrubs are much shorter than trees but are similarly woody. They usually have many stems arising at or near the base. Grasses have hollow stems and narrow leaves growing from the base. Herbs do not have woody stems. They often grow new stems and leaves every season. Vines have weak stems, and thus get support by climbing or creeping along a surface. Plants can also be grouped as flowering and non-flowering plants. Flowering plants are the biggest group of plants. They are also called angiosperms. They have roots, leaves, stems, flowers and seeds. Flowers are the reproductive structures of angiosperms. Unlike animal which can only have one kind of reproductive cells. A flower can have both male and female reproductive cells. The main male parts of a flower are the anther and the filament. Anther- bears the pollen, the powder like sticky substance that contains male reproductive cells. Filament- is a slender structure that supports the anther. Together with the anther they form the stamen. Stigma- serves as a receptacle for pollen so it has a sticky surface. It is generally at the center of the flower. Style- is a stalk-like structure that supports the stigma. Ovary- contains the ovules, which can develop into seeds upon fertilization. The stigma ,the style, and the ovary together are called carpel.
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Petals- are the colored parts of the flower. Sepals- are modified leaves that cover the petals and other parts of a flower. A group of petals is called corolla, while a group of sepals is called calyx. A flower may be complete or incomplete. A complete flower has all the important parts ,namely stamen, carpel, petals and sepals. A flower that lacks one of these parts is incomplete. An example of a complete flower is the gumamela. Pollination and Fertilization Pollination- is the transfer of pollen from an anther to the stigma in flowering plants. It enables fertilization and consequently, sexual reproduction in pants. Self pollination happens when the pollen from the anther is transferred to the stigma of the same flower. Cross pollination is when the pollen is from another flower. How is pollination possible? Wind , water, and animals are some of the agents of pollination. Some flowers such as those of trees and grasses have light and unsticky pollen that can easily be carried by the wind Water can carry pollen of some aquatic animals. Birds and bats are common pollinators in the tropics. YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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The most important agents of pollination are insects. They are usually attracted to brightly colored and scented flowers. Pollen sticks to their bodies when they visit flowers. Bees and butterflies in particular have a long mouthpart, called proboscis, which enables them to collect and transfer pollen. They also feed on nectar , a sweet liquid that some flowers produce. When a pollen grain joins with an ovule, fertilization occurs. In some plants, the fertilized eggs become new seeds: the ovary grows and become a fruit. Figure 4.5 bees and butterflies have proboscis, which enables them to transfer pollen
Activity 1. Label the parts of a flower. Choose from the words in the box. Vv
anther
carpel
filament
ovary
stamen
stigma
style
petal
gttttfff
Anther ovary
carpel
Petal style YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
stamen
filament
stigma
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Activity 2: A. Answer briefly 1. Why are flowers important to plants? ___________________________________________________________________ _________________________________________________________ 2. When is a flower a complete flower? ___________________________________________________________________ _________________________________________________________ 3. What happens when a flower is pollinated? ___________________________________________________________________ _________________________________________________________ 4. What is the difference between cross-pollination and self-pollination? ___________________________________________________________________ _________________________________________________________ 5. Why are insects important in pollination? ___________________________________________________________________ _________________________________________________________
LESSON 11: LIFE CYCLE OF A SEED PLANT Parts of a Seed A seed may look dried out and dead but it contains an embryo, which is the beginning of a new plant. When planted in the soil and with the right amount of water, sunlight, and air, it will begin to grow. This Is called germination. The hard outer coat of a seed is called testa. It protects the embryo, which includes the radical, cotyledon, and plumule. A radical is the seed root, while a plumule is the young shoot. When the seed germinates, the radical grows down into the soil, while the plumule pushes through the soil. The cotyledon, which is the first leaf or leaves of the seed, may or may not emerge from the seed. Some plants have one cotyledon; they are called monocots. Plants that have two cotyledons are called dicots.
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While the seed has yet to germinate, the embryo feeds on the endosperm, the food inside the testa. In monocots, the endosperm is separate from the cotyledon. In dicots, the cotyledons contain the endosperm. A plant can be classified as annual or perennial. An annual plant completes its life cycle in a single year. A perennial plant lives for many years. Life Cycle of a Sunflower
Have you seen sunflowers in full bloom? The sunflower is so named because of its connection to the sun. The large sunflower head with its golden-yellow petals resemble the sun. it grows during summer when it can have as much sunlight as it needs. Moreover, the sunflower head seems to follow the sun as it moves across the sky. A sunflower is an annual plant. It starts as a seed that grows in the middle of the flower head. When planted in soil and watered, it will begin to germinate. This takes between 2 to 10 days. The seed coat softens and split open. A tiny root shoots out and anchors the seed to the soil. A sprout shoots out and breaks through the soil. The sprout grows small leaves and starts to make food. Within 5 to 10 days, the sprout will become a seedling. The seedling grows fast in the next two weeks. It grows more leaves, which collect as much sunlight as possible. The leaves also let air into them. The plant absorbs water from the soil through its roots. The sunflower plant grows tall; its stalks thicken. Then green flower buds begin to show at the top of the stalks. These buds will open up into big yellow sunflowers. Insects such as butterflies and bees will pollinate the flowers. When pollen grains join the eggs inside a sunflower head, fertilization occurs and new seeds are produced. When seeds ripen, they will fall to the ground as flowers droop and the plant dies. each sunflower head holds hundreds of seeds that can be gathered and planted when summer comes again.
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Life Cycle of a Mango Tree Do you like mangoes? A mango fruit comes from a mango tree. Mango trees are native to tropical Asian countries. Most varieties grow tall and their branches spread widely. A mango tree can live very long. It can yield many fruits during its lifetime. A mango tree grows from a seed. Planted in a warm, moist are, the seed will germinate within 2 to 4 weeks. With the right amount of water and sunlight, the seedling grows taller and bigger. It also grows more leaves. Young leaves are usually red, which turn from pale green to dark green as tree grows. In 3 to 6 years, the mango tree starts to bear flowers and fruits. Mango flowers are yellowish or reddish, and attract a host of pollinators. Depending on the variety, mango fruits can be pale green or yellow marked with red when ripe. When a ripe mango fruit falls on the ground and animals such as birds and insects eat its flesh, the seed may grow into a new mango plant, completing the cycle.
Test Yourself A. Label the parts of a seed.
B. Arrange in chronological order the following stages in the life of a plant. Number the stages 1 to 5.
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The plant bears flowers.
A tiny root grows down into the soil.
The shoot pushes through the soil.
The plant bears fruits.
The seedling grows more leaves and a stronger stem.
C. Answer briefly. 1. Where do seeds come from? ___________________________________________________________________ ___________________________________________________________________
2. What is germination? ___________________________________________________________________
3. What do seeds need to germinate? ___________________________________________________________________ 4. How is a monocot different from a dicot?
___________________________________________________________________ 5. How is an annual plant different from a perennial plant? ___________________________________________________________________ YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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LESSON 12 SEED DISPERSAL Agents of Seed Dispersal Seeds have different ways of dispersing themselves. Some seeds have structures or mechanisms that help in dispersal. They also have different agents of dispersal, such as wind, water, people, animals, and gravity. Some plants have selfdispersal or mechanical means. Wind Some seeds have structure that make them fly, glide, or drift in the wind. Seeds covered with stiff wings can fly long distances. Twisted and balanced wings make seeds spin around as the wind carries them. As wings are rather heavy, seeds that have them are usually from tall trees such as sycamore and ash.
Seeds that have thinner wings glide in the air. The tropical Asian climbing gourd called Alsomitra macrocarpa, which grows in Malaysia, has the biggest winged seed.
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Alsomitra macrocarpa, Some seeds that can fly have long, feathery tails instead of wings. The flowering plant clematis produces seeds that have tails. Clematis has many kinds; one of which is called old manâ€&#x;s beard seeds have long, white silky hairs.
old manâ€&#x;s beard seeds Some seeds have fine hairs and fluffy features, which help the wind pick them up and carry them. Dandelion and thistle seeds have hairs. They are also very light.
Dandelion Some plants with pods need the wing to bend their stalks or break the pods. When the wind blows, it can make the ripe poppy fruits sway, which makes the seeds fall out. Water Water plays an important role in seed dispersal among aquatic plants. But there are other plants whose seeds get dispersed with the help of water. These plants tend to grow near the sea or other bodies of water, and have fruits or seeds YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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that can float. Coconuts are known floaters. They have woody covering and hollow center, which make them able to float over a long distance for a long time.
People and Animals Whenever you eat fruits, what do you do with the seeds? Has anyone ever asked you to keep the seeds from the fruit you ate? Farmers and plant breeders collect good seeds. Many people just throw away the seeds from the fruits they eat. If these seeds land on good soil, they may grow into new plants. Birds and other animals usually eat fleshy or juicy fruits. They may leave the seeds in another location where they consume the fruit. Some seeds have sticky or clinging structures. They may attach themselves to animal fur or human clothing and get dislodged at another location. Burr grass or cockleburs have hooks and spines.
Test Yourself A. Identify the structure that helps disperse the seeds of each plant. ___________________ 1. Alsomitra macrocapa ___________________ 2. Ash ___________________ 3. Cocklebur ___________________ 4. Coconut
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___________________ 5. Dandelion ___________________ 6. Ipil-ipil ___________________ 7. Old manâ€&#x;s beard ___________________ 8. Poppy ___________________ 9. Sycamore ___________________ 10. Thistle B. Describe how the following act as agents of seed dispersal: 1. Wind ___________________________________________________________________ ___________________________________________________________________ 2. Water ___________________________________________________________________ ___________________________________________________________________ 3. People ___________________________________________________________________ ___________________________________________________________________ 4. Animals ___________________________________________________________________ ___________________________________________________________________ 5. Gravity ___________________________________________________________________ ___________________________________________________________________
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LESSON 13: PLANT PROPAGATION Asexual Reproduction in Plants Plant Propagation is done to increase the number of a certain kind of plants. Planting seeds is the most common method of propagating plants. This is how many garden vegetables such as tomato, eggplant, and pechay are propagated. However, farmers, gardeners, and other plant growers use other ways of propagating plants. They use certain methods suited for particular plants to improve the quality of plants and their fruits. The reproduction of plants through vegetative parts such as stems, roots, and leaves is a type of asexual reproduction. Modified vegetative parts such as bulbs, corms, tubers, rhizomes, stolons, and suckers enable some plants to reproduce asexually. A bulb is an underground stem with buds protected by layers of fleshy leaves. Smaller bulbs, called offsets, grow attached to a larger bulb. Onion, garlic, lily and tulip can be grown from bulbs.
A corm looks like a bulb from the outside, but it does not grow in layers. Taro and gladiolus can be grown from corms.
A tuber is a thick and fleshy underground stem. It has nodes with buds from which new plants can grow. Potatoes are tubers. The potato „‟eyes‟‟ are actually nodes. If placed in a warm area and exposed to sunlight, the bud will turn green. Sweet potato and cassava are other examples of tubers. YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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A rhizome is a horizontal underground. It also has nodes. Ginger, asparagus, and iris can be grown from rhizomes.
A stolon or runner is a horizontal stem that produces new roots and buds at the nodes. Strawberry plants can be propagated from runners.
A sucker is a young plant that sprouts from the horizontal roots of the parent plant. It can be separated from the parent plant and planted in another place. Transplanting a sucker should be done carefully as this can disturb the parent plant. Banana plants can be propagated from suckers.
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Artificial Propagation Propagation that is carried out by people is called artificial propagation. Different methods of artificial propagation include cutting, grafting, budding and layering. Cutting Cutting is a method in which a portion of the parent plant is cut so that it will regenerate itself into a new plant. The portion of the plant, is also called cutting, may be a leaf, a stem, or roots. Stem cuttings can be taken from woody plants and herbaceous plants. Leaf cuttings are used only for selected indoor plants such as begonia and African violet. Root cuttings can be taken from woody plants and perennials. Using a sharp blade to take cuttings reduces injury to the parent plant. One-third to one-half of the cutting is placed in water or soil depending on the plant. Grafting Grafting is joining its two plant parts so that they will grow as one plant. The upper part of a grafted plant is called scion, while the bottom part is called rootstock, or simply, stock. The scion may be a bud, a twig, a stem, a shoot, or a fragment of a root. The sotck serves as the root system of the new plant. There are many types of grafting. The types differ in the sizes of scion and stock as well as the plant part used as scion. In bark grafting, for example, vertical slits are made on the bark of the stock where multiple scions are inserted. What is common to all the types of grafting is that both scion and stock should be healthy. They must be free from pests and diseases many fruit tress such as avocado and lanzones can be propagated by grafting.
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Budding Budding is a form of grafting, in which only a single bud is inserted into the stock. There are many types of budding. One of these is the shield or T budding. A bud with a bit of wood is cut from one plant. A T-shape is cut on the bark of the stock. The bark is pulled back, and the budis inserted and tied.
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Citrus fruit are commonly propagated by budding. Roses and other ornamental plants can also be propagated by budding. Layering Layering is a method in which roots are made to develop on a stem while the stem is still attached to the parent plant. Runners lend themselves well to propagation by layering. In simple layering, a stem of a plant is bent to the ground and covered with soil. In mound layering, soil is mounded over new shoots as they grow. In air layering, a portion of the stem is cut, opened, and wrapped with a rooting medium such as moss.
Test Yourself A. Identify the vegetative plant from which each plant can be propagated. 1. Asparagus 2. banana 3. cassava 4. garlic 5. iris 6. lily 7. strawberry 8. sweet potato 9. taro 10. tulip
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B. Explain in your own words each method of artificial propagation. 1. budding
2. cutting
3. grafting
4. layering
UNIT 3: MATTER AND ENERGY Lesson 14: Properties of Matter Matter is all around you .It is anything that has mass and occupies space. Mass is the amount of particles present in an object. It can be measured by using a platform balance or a weighing scale. It can be expressed in grams or kilograms. The space that matter occupies is called volume. Mass and volume are properties of matter. A property of matter describes its nature or behaviour. Properties that can be observed such as size ,shape, color and texture are called physical properties. The different properties of matter determine its uses. Some objects or materials have properties that set them apart from other materials.
Porosity is the ability of a material to absorb fluids. Cotton cloth, and sponge are porous objects.
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Elasticity is the ability of a material to be stretched and return to its original shape. Rubber bands and garters are elastic.
Ductility is the ability of a material to be drawn into very thin wires without breaking .Copper is ductile.
Malleability is the ability of a material to be molded or shaped without breaking. Steel is malleable.
Solubility is the ability of a substance to dissolve in another substance. Coffee granules and salt are both soluble in water.
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Brittleness is the ability of a material to break easily. Ceramic and glass are brittle.
Hardness is the ability of a material to resist breaking or scratching .Diamond is the hardest naturally occurring material on Earth. No other material can scratch it except itself. Talc, on the other hand, is the softest material.
Luster is the ability of a material to shine or reflect light. Mirror marble, and steel are lustrous materials.
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Activity. Write each material under the correct property. You may write a material under more than one property.
Porosit y
Powdered milk
diamond
ceramic vase aluminum
Tissue paper
rubber balloon
marble
copper
Sugar
gold
glass jar
emerald
Clay
rug
iron
Brittlen ess
Malleability
Ductility
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Elasticity
Hardnes s
Luste r
Solub ility
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LESSON 15-SOLIDS Do you have the items illustrated below in your house? Describe each item. Does it have mass? Does it occupy space? What is its shape?
Cereals, butter, sugar ball, chocolate bar, paper towel and laundry soap are al solids. A solid has mass, and a definite shape and volume. Take a chocolate bar as an example. You can find its mass by weighing the chocolate or by looking for it in the label. The chocolate bar is rectangular in shape. How do you determine its volume? Volume of Regular Solids Recall that volume is the space that matter occupies. The chocolate bar has a definite shape. Solids that have definite shapes are called regular solids. You may use a ruler, a meterstick or a measuring tape to measure the dimensions (length, width, height, diameter ) of a regular solid. Given the dimensions of the solid, you may solve for its volume.
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To solve for the volume of a rectangular solid, use the following formula: V= l x w x h Where V= volume L=length W=width H= height The formulas for the volume of other solids are given in Table 6.1. Table 6.1 Volume of Some Solids Solid
Name
Cube
Example
Formula For Volume V=e x e x e Where e= measure of an edge
V= x r ² x h, Where r=radius Cylinder
And h= height
V=4/3 x x rÂł Sphere
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r=
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Volume of Irregular Solids Solids that do not have definite shapes are irregular solids. A stone is an example of an irregular solid. You can easily determine its mass but not its volume. An irregular solid does not have dimensions that can be measure using a ruler, a meterstick, or a measuring tape. To find the volume of an irregular solid, use the displacement method in which you use a graduated cylinder. A graduated cylinder is glassware with markings. It is commonly used in the laboratory to measure volumes of liquid. The steps in the displacement method are as follows. 1. Pour a certain amount of water into the graduated cylinder. Take note of the initial water level. 2. Carefully drop the irregular solid in the graduated cylinder. 3.Read the final water level. 4. Subtract the initial water level from the final water level. The difference in the volumes is the volume of the irregular solid.
How do Particles of Solid Look?
Figure 5. 1. Particles of solid Solids have definite shapes and sizes because their particles are packed closely. The particles in a solid have very strong resistance against forces to change the shape and size of the solid. They cannot be compressed further.
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Figure 5.2.Examples of solids Activity 1 Find the volume of each object.
6 cm
11 10 cm G 8 cm
12 12 cm Gg 10 cm 66 6 cm
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G5 cm
Ff 6 cm
14 14 cm Frr 10 cm 20 cm
B. Complete the table Initial Water Level
Final Water level
10 ml 20 ml 20 ml 30 ml 45 ml
25 ml 47 ml
Volume of the Irregular Solid
23 ml 58 ml 18 ml
Go Beyond Are you familiar with Aesopâ€&#x;s fable the crow and the pitcher? In the fable, a thirsty crow came upon a pitcher. However, the pitcher had only very little water that when the crow put is beak into it, he could not reach enough to get a drink. Can you tell what the crow did? The crow took a pebble and dropped it into the pitcher. It saw the water rise. It kept on dropping pebbles until the water had risen high enough for the crow to drink. What method did the crow in Aesopâ€&#x;s fable use?
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Lesson 16: Liquids Targets:
To describe liquids To show that liquids have mass and definite volume To measure the volume of liquids.
Do you have the items illustrated below in your house? Describe each item. Does it have mass? Does it occupy space? What is its shape?
Water, fresh milk, juices and gasoline are all liquids. A liquid has mass and a definite volume. You can find the mass of a liquid by weighing the liquid and its container. Find the mass of the empty container, and then subtract this from the mass of the liquid and its container. The difference is the mass of the liquid. There are several devices that you can use to find the volume of a liquid. Measuring spoons and cups are commonly used in the kitchen. In the laboratory, a graduated cylinder or a beaker is used. For medicine, particularly those intended for infants, a medicine dropper is used. Some containers such as baby feeding bottles have volume markers on them. Can you think of other devices that can be used to measure the volume of a liquid?
Figure 5.3 Different devices for measuring the volume of a liquid YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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There are different units used for liquid volume. When measuring very small liquid volume, the most appropriate units are the millilitre (mL) and the fluid ounce (fl.oz.). There are about 20 drops in 1 ml of liquid. For large volumes of liquids, use lite(L) or gallon (gal.). Milliliter and liter are metric units, while fluid ounce and gallon are English units of volume. The particles of liquids are not that close to each other. This is why liquids are not that close to each other. This is why liquids do not have definite shapes. They take the shape of their containers. Moreover, they can flow. Because liquids can flow, they are also referred to as liquids .
Figure 5.4. Particles of liquids
Activity A. Which unit of volume is most appropriate for each liquid? Write mL or L on the space provided.
_________1. Chocolate syrup
_________2. Gasoline in a tank
_________3. Infant cough syrup
_________4.water in a jug
_________5. Water in a swimming pool
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B. Draw different containers used for the following liquids. 1. Alcohol
3. Fresh milk
2. Cooking oil
4. Fruit juice
LESSON 17: GASES
What is inside a scuba diverâ€&#x;s diving cylinder? Can the cylinder contain more gas than the volume of the cylinder?
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One kind of matter that surrounds you is gas. The air around you is a mixture of gases, including nitrogen, oxygen, water vapour, carbon dioxide, neon, helium and methane. A gas has mass, but it has neither definite volume nor shape. How do particles of gases look? The particles in gases are far apart from one another. They can move freely. They take the shape of the containers. Like liquids gases can flow. They are also classified s fluids. Gases can be compressed. A diving cylinder contains oxygen-enriched air mix, allowing a diver to breathe underwater. It usually has a volume of only 3 liters, but it can contain 600 liters of gases by compression. Gases can expand. When someone is looking in your home, can you tell what is being cooked even before you reach your kitchen? The smell of the food can travel because of diffusion. Diffusion is a process whereby particles of solids, liquids or gases interact or mix. In gases, diffusion happens spontaneously. You do not have to do anything to mix gases around you. Diffusion also happens quickly because the particles in gases move quickly. Leave a bottle of perfume open. How long does ot take before the room is filled with the smell of the perfume? Activity A. Write true if the statement is correct.Write False if the statement is correct. _______________1. Gases can flow. _______________2. Gases have definite volume. _______________3. Gases have definite shape. _______________4. Gases have mass. _______________5. Gases can be diffused. YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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B. Find out from the references ( science books, encyclopedias, internet) the use of each gas. 1. Oxygen ______________________________________________________________ ___________________________________________________________________ 2.helium____________________________________________________________ ___________________________________________________________________ 3.nitrogen ______________________________________________________________ ___________________________________________________________________ 4.neon ___________________________________________________________________ ___________________________________________________________________ 5.methane ___________________________________________________________________ ___________________________________________________________________
LESSON 18: HEAT People use heat every day. They use it to cook and preserve food. They use it to dry and iron clothes. People who live in cold places use heaters to warm their homes. What is heat?
Recall that kinetic energy is energy in motion. Heat, also called thermal energy is generated when particles of matter move back and forth, or vibrate. Hence, it is a form of kinetic energy. When the particles move faster, more heat is generated. The particles of hot water are moving than those of cold water. When a substance is heated, its temperature rises. Temperature tells how hot or cold a substance is.
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Figure 6.1. Particles of hot water and of cold water
Sources of heat Heat comes from natural or artificial sources. The sun is the major source of heat on Earth. Earth itself generates heat called geothermal energy. Burning coal generates heat. Rub your hands together, then touch your face. How does it feel? Rubbing two things together also generates heat. Most sources of light are also sources of heat. These include torches, lamps and candles. Household items that generate heat include oven, stove and flat iron.
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Figure 6.2 Different het sources Effects of Heat Heat causes changes in matter. It can cause physical or chemical changes. A physical change is a change in physical property such as size, shape and phase. A chemical change is a change in a composition of matter. It involves the formation of a new substance. Physical Changes Recall that matter can exist as a solid, a liquid, or a gas. Application or removal of heat ca change the phase of matter. Take water as an example. Water at room temperature is a liquid. If you put it inside the freezer, it will turn to ice, which is a solid. If you boil water, it will become steam or water vapour, which is a gas. A change in phase is a physical change. The change of phase from solid to liquid is called melting, while that from liquid to solid is freezing. The change of phase from liquid to gas is called evaporation, while that from gas to liquid is condensation. The change of phase from solid to gas without passing through the liquid phase is called sublimation. Its reverse is called desublimation. Look at the pictures below. What process is taking place in each situation?
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Figure 6.3. Phase changes
Chemical Changes Heat is involved in chemical changes. When you burn wood, for example heat is released. The composition of wood is changed. Burning or combustion is a chemical reaction between a fuel and an oxidant, usually oxygen giving off heat and light.
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Figure 6.4. Chemical changes Safety precautions Involving Flammable or Combustible Substances Some substances are flammable or combustible. They can easily catch fire. They ignite at a certain temperatures. Gasoline and alcohol are flammable substances. Potential ignition sources include lighter, candle, matchstick, electrical switch and static electricity.
Here are some safety precautions involving flammable or combustible substances 1. Store or dispose of combustible substances properly. Store them in a wellventilated place to prevent build-up of heat. 2. Check all the liquefied petroleum gas (LPG) tank and the connecting hose to the stove regularly for leaks. 3. Turn off all electrical appliances when not in use. Better still, unplug them from sockets. 4. Do not throw a lighted matchstick. 5. Do not leave any burning wood or candle unattended.
Activity A. What is the effect of applying heat on each substance? Identify the process involved in any change in the substance? 1. butter_______________ 2. candle_______________ YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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3. mothball_____________ 4. salt water_____________ 5. crayon_______________ B. 1.What are the uses of heat? ___________________________________________________________________ ___________________________________________________________________ 2. What are the natural sources of heat? ___________________________________________________________________ ___________________________________________________________________ 3.What are some artificial sources of heat? ___________________________________________________________________ ___________________________________________________________________
4. What are the effects of heat on matter?
___________________________________________________________________ ___________________________________________________________________ 5. How should you handle flammable materials?
___________________________________________________________________
LESSON 19: TEMPERATURE Recall that matter is made up of particles that are constantly moving. Hence they have kinetic energy. The measure of the average kinetic energy of the particles in a material is called temperature. When t eh particles are moving slowly the temperature is low. When they are moving fast the temperature is high.
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You cannot see the particles in a material moving but you can measure the temperature of the material. Temperature is the degree of hotness or coldness of a material or a body. It can be measure using a thermometer. The two commonly used scales of temperature are the Fahrenheit scale and the Celsius scale.
Figure. 6.5 The Celsius and Fahrenheit temperature scales The Fahrenheit scale was proposed by Daniel Gabriel Fahrenheit the German physicist who invented the first accurate thermometer in 1706.Each unit of change is called a degree Fahrenheit (˚F) the boiling point of water on the Fahrenheit scale is 212 ˚F while the freezing point is 32 ˚F. The Celsius scale on the other hand, was named after Anders Celsius, the Swedish astronomer who developed a similar scale. Each unit of change is called a degree Celsius (˚C).The boiling point of water on the Celsius scale is 100˚C, while the freezing point is 0˚C. When you apply heat on a body, you may notice that the temperature rises. Heat and temperature are related, but they are not the same. Two bodies may have the Same temperature, but they may differ in the amount of heat. Heat depends on the speed, the number and the type of particles in a body. Temperature does not depend on size or type of matter. A mug of water might have the same temperature as a pot of water, but the pot of water has more heat because it has more water. YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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Activity Write true if the statement is correct .Write false if it I not. _________1. The faster the particles move, the higher the temperature of an object is. _________2. A degree in the Fahrenheit scale has the same value as a degree in the Celsius scale. ________3.The boiling point of water in the Celsius scale is higher than that in the Fahrenheit scale. ________4. A rise in temperature indicates a higher amount of heat in a
object.
________5. A decrease in the level of colored liquid in a thermometer tells you that the temperature is falling. Go Beyond
The normal body temperature is 98.6 F or 37 C. You can convert a temperature reading in Fahrenheit to Celsius, and vice versa.  To convert Fahrenheit to Celsius, subtract 32 from the Fahrenheit temperature. Then multiply the result by 5/9.  To convert Celsius to Fahrenheit, multiply the Celsius temperature by 9/5.Then add 32 to the result.
LESSON 20: HEAT TRANSFER
The sun is very far from the earth, yet you can feel its heat. Heat flows from a hotter body, which is the Sun, to a cooler body, which is your body. Heat transfer involves the amount of heat from the source and the flow of heat transferred. Hot objects like the Sun, give off infrared light that can travel in waves through empty space and air. When infrared radiation is absorbed by a body, it is changed into heat. This method of heat transfer is called radiation. ` The other method by which heat is transferred from a hotter body to a cooler body are convection and conduction. YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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You must have observed that boiling water moves in a circular pattern. The continuous exchange of heated and cooled liquid produces circulation. This movement is called convection current. This method of heat transfer I called convection.
Figure 6.6 Heat transfer by convection Look at the figure 6.7. Heat travels from the hotter body (flame) and is absorbed by the cooler body (metal spoon), which in turn gets hot. This method of heat transfer is called conduction.
Figure 6.7 I conduction, energy is absorbed. Materials that conduct heat are called conductors. Most metals are good conductors of heat. They easily get hot when heated. That is why people commonly use metals as cooking wares or utensils. However metals can cause burns when touched by or held with bare hands. You will notice that the handles of the metal wares are made of wood or rubberized materials. Wood or rubberized materials are materials that do not conduct heat. They are called insulators. Figure6.8. What are pot holders and handles of cooking wares made of? Can you name other examples of conductors? How about insulators? What must you do to avoid being burnt when holding hot objects? YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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Activity A. Choose the letter of the correct method of heat transfer in each situation. a. conduction b. convection c. radiation ___________1. Drying of corn grains under the sun. ___________2. Heatin a metal spoon by placing it in a cup. ___________3. Steaming a fish ___________4. Baking a fruitcake ___________5. Ironing clothes ___________6. Frying a fish ___________7. Boiling a cup of water B. Classify each material or object as conductor or insulator of heat. _______________1. Copper _______________2. Cloth _______________3. Wood _______________6. Rubber mat _______________5. Tin can _______________6. Aluminium _______________7. Glass ______________8. Mittens ______________9. Umbrella ______________10. Slippers
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UNIT 1V EARTH AND SPACE
LESSON 21: SOIL EROSION Targets: To describe the different layers of soil To describe soil erosion To identify some causes of soil erosion To explain how the contour or shape of the land affects the amount of soil being washed away
Soil is a thin surface of matter that covers of the land area. It is made up of broken pieces of rocks, organic materials such as decayed plants and animals, air and water. It is one of the most important resources that support human existence.
Soil has three layers: topsoil, subsoil, and bedrock. Each layer is different from the others because it has a specific color, texture and mineral content.
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The uppermost horizon of soil forms the nutrient-rich topsoil. It contains a lot of loam, which makes plants grow well. It has enough air and water to sustain living things. It is rich in organic materials such as leaves and animal manure. Below the topsoil lies the subsoil, which contains minerals that are pressed and moved down from the topsoil. Roots of big plants may reach the subsoil. This layer has less amount of air and water. The dry subsoil is often found with weathered parent rock, which is rich in lime, granite, and marbles. A parent rock is a rock from which another rock or soil is formed. Rock fragments are found below the subsoil. They make up the layer called bedrock. The bedrock forms the foundation of hard rock layers of parent rocks. Rock fragments are often used in constructing buildings, roads and bridges. Some sculptures are also carved from rocks. Although land surface of Earth appears to be permanent, landscapes are always changing. These changes are caused by strong natural forces such as water and wind. These natural forces can carry soil from one place to another. This process of transferring or carrying soil from one place to another is called soil erosion. Where would the soil go when landslides on riverbanks take place? What causes the sand particles to move out of place? What other forces can bring about soil erosion?
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Causes of Soil Erosion Forces that bring about soil erosion are called agents of erosion. They include running water, rainfall, glaciers and wind.
Flowing water from rivers and rainfall carries particles of soil and rocks to the sea. The rocks that flow with the river grind against the bottom and the sides of the river. The grinding carves a valley, making the sides steep.
Glaciers can be an effective agent of erosion because they can carry larger rocks than running water can. Fig. 7.2 erosion by running water Figure 7.3. Glaciers The force of the wind can contribute greatly to soil erosion, particularly in areas covered in sand.hen a strong wind blows, sand particles from the beach is desert pile up somewhere else. The particles of sand form sand dunes. Sand dunes may be occupied by some animals as their homes.
Fig.4 sand dunes
What will happen to the particles of the topsoil when rain pours heavily? In which landform will more particles be carried away? Why? YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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The slope of the land affects the amount of sol being washed away. The steeper the slope of the land, the greater the amount of soil can be carried downhill.
Activity 1 Put a check (/) on the blank if the activity contributes to soil erosion. Put a cross (x) if it does not. ____1. Planting trees in the mountains ____2. Plowing a hill by following its shape or contour ____3. Building an establishment for commercial use ____4. Letting animals graze in an open area. ____5. Mining ____6. Driving through sand in deserts ____7. Planting crops and vegetation ____8. Digging the ground ____9. Cutting down trees ____10. Quarrying
Go beyond The Chocolate Hills in Bohol are a famous tourist attraction in the Philippines. Their formation has been debated upon by geologists. Some said the hills were formed ages ago by the „‟uplift‟‟ of coral deposits and the action of rain, water and erosion.‟‟ Others said that the grassy hills were once corals that erupted from the sea in a massive geologic shift. Wind and water put on the finishing touches over hundreds of thousand years.‟‟
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Chocolate hills in Bohol, Philippines
LESSON 22: EFFECTS OF SOIL EROSION Target;  Identify the effects of soil erosion on the shape/contour of the land, condition of the soil, condition of water, plants, animals and people. Erosion affects the shape or contour of the land. How?
Limestone cliffs in Coron, Palawan Erosion is a gradual process. It takes million of years for waves and water, which carries sand and pebbles, to carve a hole in the mountain and form a river. However, extreme events can remove large amounts of soil, and change landscape quickly. YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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The strong forces of water and wind can affect the surface of land overtime. The continues blowing of the wind and running of water can result in the formation of different landforms. A good example that erosion changes overtime is the limestone cliffs in Coron, Palawan. Believed to be formed 260 million years ago, these years are made of limestone. They were formed more than 400 meters above sea level. They were uplifted by an underwater quake 30 million years ago from the continental crust of old China. Erosion by waves and monsoon rains make the cliffs what they are today. A tunnel like entry to Sohoton Natural Bridge in Basey, Western Samar was formed by the flowing water of the river. The natural bridge connects two mountain ridges spanning the Sohoton river.
Sohoton Natural Bridge of Basey, Western Samar Biri Island in Northern Samar has wonderful rock formations of sandstone, siltstone, mudstone and conglomerate rocks. Formed million years ago, they were brought about by erosion and removal of rock particles by the action of wind ,water and waves.
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Biri island, Northern Samar
The white dunes in Paoay, Ilocos Norte formed from sand particles that carried away and deposited by over time.
sand were were wind
The Callao Cave in Penablanca Cagayan was naturally built with a widespread limestone plarform , forming channels of caves.
The Philippines has many other great geological features brought about by erosion for the past million years. The Tagoloan River has carved out hundreds of meters of steep slopes, forming a grand canyon in Bukidnon. The Tagoloan Canyon is made of piled up gravel, and silt. The steep massive limestone gorge in Minalungao, General Tinio, Nueva Ecija was also carved by erosion.
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Tagoloan canyon in Bukidnon Soil erosion lowers the land surface of the continents. Every year, the river carries billions of tons of sediments to the oceans. This transfer of silt and other soil particles is enough to lower or submerge the land surface of the continents by 3 centimeters every 1000 years. Soil erosion affects the living conditions of the people. Erosion can change the slope of the land. Heavy rainfalls resulting in landslides or a mudslide often occur along mountainous area. When a landslide or a mudslide happens, residents in the low-lying areas experience great damage. Crops and other properties are destroyed. Some people lose their homes, or worse, lose their lives in landslides or mudslides. Soil erosion affects plants and animals. Mineral sin the soil are washed away by erosion. The barren and infertile soil affects crops and other vegetation. Because less plants are produced by infertile soil, there is also less food for animals. Can you think of other effects of soil erosion?
Activity 1 A. Give the effects of soil erosion. Write the letter of the best answer on the blank. a. soil erosion affects plants and animals. b. soil erosion affects peopleâ€&#x;s lives. c. soil erosion lowers the land surface of the continents. d. soil erosion changes land surfaces. ______1. Plants cannot grow on infertile land. ______2. Caves are formed. YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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______3. Mudslides occur. ______4. Livestock of farmers are affected. ______5. Limestone cliffs are formed.
B. Write True if the statement is correct. Write False if it is not correct. ____________1. Soil erosion can form caves. ____________2. Soil erosion has no benefit at all. ____________3. Soil erosion creates landforms. ____________4. Soil erosion Changes the shape of the land. ____________5. Soil erosion does not destroy landscapes.
Go Beyond Landslide occurs when a large amount of land has been eroded. Sometimes it is called a mudslide, particularly if the major cause of erosion is heavy rainfall. In 2006, a mudslide occurred in Southern Leyte. Hundreds of houses were covered with mud within a short period of time. At least 1000 persons died.
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LESSON 24: WEATHER The atmosphere is a blanket of air that covers Earth. The condition of the atmosphere for a short period of time is called weather. Climate is the condition of the atmosphere for a long period of time. What is the climate in your are? What is the weather today? The weather may be sunny, windy, cloudy, rainy, or stormy. It is affected by several factors such as air temperature, humidity, wind speed and direction, cloudiness and amount of rainfall. These factors are also called elements of weather. Meteorologists, the scientists who study the earth‟s atmosphere, use these elements to predict the weather .
Air Temperature Air temperature tells how hot or called the atmosphere is. Since temperature changes a lot during the day, meteorologists use a thermograph, a device that records temperature automatically and continuously.
Air Pressure Air pressure is the weight of air pressing down the earth‟s surface .It is measured by an instrument called a barometer. One type of barometer is the mercury barometer. A rise in the mercury level of the barometer means high air pressure. A fall in the mercury level means low pressure. Low air pressure is usually associate with bad weather.
Humidity The atmosphere always contains moisture in the form of water vapor. As the Sun heats land and water surfaces; water evaporates into water vapor. Water vapor rises and is suspended in the upper atmosphere. The amount of moisture that the atmosphere contains is called humidity. It is measured with a hygrometer. Humidity depends on air temperature. When air temperature rises, the air becomes humid or saturated with water vapor. This makes people perspire a lot. When air temperature drops excess water vapor condenses, it forms dew on surfaces such as blades of grass or a window pane. Wind Speed and Direction Wind is moving air. It is caused by the rising of warm air and sinking of cold air. When the Sun heats up the earth‟s surface, water is turned into vapor or warm air. Warm air rises, allowing the cooler air to move and take its place. Wind only blows where there is a difference in air temperature and air pressure. Wind that blows gently is called a breeze. An anemometer is an YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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instrument used to measure wind speed. A wind vane is used to determine the direction of the wind. Cloudiness A cloud is visible mass of water droplets in the atmosphere. The weather depends on the amount of clouds covering the sky. There are different types of clouds; each type indicates a kind of weather. Thin, high and light clouds indicate a fine or fair weather. Thick,low and dark clouds bring heavy rains or storm. Cumulus clouds are light and puffy. Cirrus clouds are very thin, curly or feathery. Stratus clouds look like a gray blanket. Nimbus clouds are very dark. A ceilometer measures the height of the clouds. A nephometer measures the cloudiness in the atmosphere. Amount of rainfall When clouds get too heavy with water droplets, they fall as rain. A rain gauge measures how much rain has fallen.
Weather Forecasting Meteorologists use different weather instruments in studying the condition of the atmosphere. From the data they gathered and analyzed, they predict the weather. This act of predicting the weather is called weather forecasting. A weather forecast tells exactly what the weather will be for the day or the next few days. In the Philippines, the official weather bureau is the Philippine Atmospheric Geophysical Astronomical Services administration (PAGASA) . The weather forecast is made known to the public through various media such as television, radio, print and internet.
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Activity Match the descriptions in Column A with the correct words in Column B.Write the letter of the correct answer on the blank. A B ________1. It measures the speed of the wind a. Anemometer ________2.It is a blanket of air that covers earth. b. atmosphere ________3.It is the condition of the atmosphere c. ceilometer for a short period of time ________4. It is the condition of the atmosphere d. Climate for a long period of time ________5. It measures how hot or cold the atmosphere In the atmosphere is. e. Hygrometer ________6. It measure the amount of moisture f. Meteorologist in the atmosphere g. rain gauge ________7. It determines the direction of the wind h. thermograph ________8. It measures the amount of rainfall i. Weather ________9. It measures the height of clouds j. Wind vane ________10. It is a scientist who studies the earth‟s atmosphere
CHAPTER 8: EARTH,THE MOON AND THE SUN LESSON 25: MOVEMENTS OF EARTH Earth is moving on its axis and around the sun through an imaginary path called orbit. Earth’s rotation
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Earth moves on an imaginary line called axis. This movement is called rotation. Earth is tilted about 23.5 degrees north as it rotates. Its rotation is constant as it revolves around the sun. This explains the rising and setting of the Sun, and the occurrence of day and night. The sunrise and sunset are independent of the motion of the sun. They are dependent on the rotation of earth and your position on the planet. Earth rotates on its axis from east to west. It takes about 24 hours to make one complete rotation. The earth‟s tilt affects the length of day and night. As earth rotates on its axis and revolves around the sun, the amount of sunlight a certain area receives changes.
Earth’s revolution Earth revolves around the Sun, following an elliptical orbit. One earth revolution takes 365 ¼ days, which is equivalent to one year. A leap year takes place every four years. During a leap year. February has 29 days instead of its usual 28 days. Earth‟s revolution affects climate. This explains the seasons experienced in different parts of Earth.
Some parts of earth experience four seasons: winter, spring, summer and autumn. The Northern hemisphere experiences summer when it is tilted towards the Sun, and winter when it is tilted away from the Sun. When the Northern Hemisphere is experiencing summer, it is winter in the Southern Hemisphere and vice versa.
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Activity Read each statement .Write RT if it is related to Earth‟s rotation, or RV if it is related to Earth‟s revolution. __________1. Earth is tilted about 23.5 degrees north as it rotates. __________2. Countries experiences different seasons. __________3. A leap year happens very four years. _________4. One side of earth receives light while the other is in darkness. _________5. The orbit of earth is elliptical in shape.
LESSON 26 : MOON AND ITS PHASES The Moon is the only natural satellite of Earth and is known as earth‟s nearest neighbor in space. It has a diameter of 3,476 kilometres. It has craters, lava plains, mountains and valleys. Scientists believe that the craters were formed between 3.5 to 4. Billion years ago by falling meteors. That hit the Moon‟s surface. The moon does not have an atmosphere or water on it. The moon travels around earth in an orbit. It takes 27 days to go around earth. It revolves around earth from west to east. The moon seems to change its shape as it revolves around Earth. These changes are visible at night. Different portions of the lighted part of the Moon can be seen
The phases of the Moon are the different ways the Moon looks from Earth over the period of approximately a month. As the Moon orbits around the Earth, the half of the Moon that faces the Sun will be lit up. A person standing on the Earth will see a different portion of the lit half of the Moon depending on the position of the Moon in its orbit around Earth. The different shapes of the lit portion of the Moon that can be seen from Earth are known as phases of the Moon. Each phase repeats itself every 29.5 days, approximately. The same half of the Moon always faces the Earth, so the phases will always occur over the same half of the Moon's surface. There are 8 phases that the moon goes through.
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A new moon is when the Moon cannot be seen because we are looking at the
unlit half of the Moon. The new moon phase occurs when the Moon is directly between the Earth and Sun.
A waxing crescent moon is when the Moon looks like the crescent and the crescent increases ("waxes") in size from one day to the next.
The first quarter moon (or a half moon) is when half of the lit portion of the Moon is visible after the waxing crescent phase.
A waxing gibbous moon occurs when more than half of the lit portion of the
Moon can be seen and the shape increases ("waxes") in size from one day to the next. The waxing gibbous phase occurs between the first quarter and full moon phases.
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A full moon is when can see the entire lit portion of the Moon. The full
moon phase occurs when the Moon is on the opposite side of the Earth from the
Sun.
A waning gibbous moon occurs when more than half of the lit portion of the
Moon can be seen and the shape decreases ("wanes") in size from one day to the next. The waning gibbous phase occurs between the full moon and third quarter phases.
The last quarter moon (or a half moon) is when half of the lit portion of the Moon is visible after the waning gibbous phase.
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A waning crescent moon is when the Moon looks like the crescent and the
crescent decreases ("wanes") in size from one day to the next.
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LESSON 27: ECLIPSES An eclipse is the darkening of a heavenly body by another body. This happens when Earth, the Moon and the Sun form a straight line. An eclipse may be lunar or solar. Lunar Eclipse An eclipse of the moon is called lunar eclipse. When a lunar eclipse occurs, the moon is a little bit above or below the shadow of earth. As he Moves out of the shadow of earth, it becomes brighter again..When the moon passes behind earth, earth covers the entire lighted side of the moon. The Moon becomes totally dark because earth is much bigger than the Moon. In a lunar eclipse, the Moon may appear in colors the earthâ€&#x;s atmosphere refracts or bend sunlight, giving light to the Moon. When this happens, the moon appears dark red, rust, brick-red, or bright copper red or even orange. This happens during the full moon phase.
Solar Eclipse An eclipse of the Sun is called solar eclipse. As the Moon blocks the light coming from the sun, its shadow falls on earth. In this case, a small portion of earth experiences darkness during daytime. A solar eclipse may be partial or total depending on the turns or shifts of the Moon and earth each year.
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Activity Write LE on the blank if the statement is related to lunar eclipse. Write SE if it is related to solar eclipse. _________1. This is an eclipse of the Moon. _________2. This is an eclipse in which the moon blocks the light coming from the Sun _________3. Use a very dark welderâ€&#x;s mask in viewing this eclipse. _________4. The moon appears dark red, rust, brick-red or even orange. _________5. The Moon passes behind Earth; Earth consequently covers the Moon.
LESSON 28: TIDES As earth rotates on its axis, and the Moon and the Sun change their positions, tides occur. Tides are the rising and falling of large bodies of water. The rising and falling of ocean or seawater is caused by the difference in the gravitational attraction between Earth and the Moon.
Figure 8.15.The occurrence of tides The moon exerts a gravitational force on Earth. This force attracts the water part of earth, causing tides. The Moonâ€&#x;s gravity pulls on the surface of the ocean until it moves toward the direction of the Moon. When water has reached its highest point, it is called high tide. High tide occurs on the other side of earth. As earth rotates, it YOUNG JI INTERNATIONAL SCHOOL/COLLEGE
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creates a force that pulls water away from earth. In between these areas, the are facing the Moon and the one on the other side of it experience low tides.
During a lunar eclipse , the sun and moon are on the opposite side of earth, in which the sun tends to cancel some of the effect that the moon has on earth. However, high tide can still occur during a lunar eclipse, but it will be slightly less than the tide when the sun is not on the opposite side of the earth. Spring Tide A spring tide does not have anything to do with the spring season. Spring tides are very strong and unusually high tides. The Moon is positioned very close to earth. Both the Sun and the moonâ€&#x;s gravitational force pull the earthâ€&#x;s waters. Spring tide happens during full moons and new moons.
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Neap Tides Unlike spring tides, neap tides are weak tides. They happen when the gravitational forces of the Moon and the Sun are pulling the Earth‟s waters away from each other. They occur during quarter moons. Activity Write True if the statement is correct .Write false if it is not. __________1. Earth moves from east to west. __________2. It takes longer for earth to revolve around the Sun. __________3. The earth‟s axis is always tilted as it rotates and revolves around the sun. __________4. A revolution takes 366 ¼ days
BIBLIOGRAPHY: Adaon, M. S & Cabrido E. N.(2011). Science Web. Quezon City. C&E Publishing, Inc. Other sources: http://biology.about.com/od/organsystems/ss/skeletal-system.htm http://www.innerbody.com/image/skelfov.html http://hes.ucfsd.org/gclaypo/skelweb/skel01.html#cravert http://www.healthline.com/human-body-maps/skeletal-system
http://www3.canisius.edu/~grandem/butterflylifecycle/The_Lifecycle_of_a_But terfly_ print.html http://www.innerbody.com/image/digeov.html http://biology.about.com/od/organsystems/ss/skeletal-system.html
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