UNIT 2. RESPIRATORY & EXCRETORY SYSTEMS.

1

UNIT 2. NUTRITION 2.

RESPIRATORY & EXCRETORY SYSTEMS SCIENCE 6.

CONTENTS: 1.– RESPIRATORY SYSTEM: 1.1.– Respiratory tract and lungs 1.2.– Movements.

1.3.– Respiration in lungs .

1.4.– Respiration in cells.

1.5.– Protect your health: infections, allergies, asthma...

2.– EXCRETION: 2.1.– Urinary system: components and process.

2.2.– Excretion through skin.

2.3.– Protect your health.

C.E.I.P. SANTA ANA (Madridejos)

RESPIRATION is the process in which our body gets oxygen from the air. O2 passes through the blood to every cell to get energy, and CO2 is expelled to the exterior.

1

2 NASAL CAVITY 1.– RESPIRATORY SYSTEM. 1.1.A.- Respiratory tract or airways is a tube NOSTRILS that connects the nose and mouth with lungs.

MOUTH It has different parts: a.– Nostrils, nasal cavity and mouth are LARYNX openings where air gets in and out of the body. b.– Pharynx the place where mouth and nasal cavity join.

WINDPIPE or

PHARYNX

TRACHEA

c.– Larynx has got vocal cords to speak. d.– Trachea or windpipe is a rigid tube with rings to prevent smashing. e.– Two bronchi are two tubes that enter into each lung. f.– Bronchioles. Bronchi are divided into lots of bronchioles that transport air to every alveoli (microscopic sacs where blood from the capillaries gets O2 and releases CO2)

LEFT LUNG

RIGHT LUNG

RIB LEFT BRONCHUS

RIGHT BRONCHUS

INTERCOSTAL MUSCLES

BRONCHIOLES

2 DIAPHRAGM

1.1.B.– Lungs are the essential respiration organs. They are inside the thorax and protected by ribs. Their function is to transport the oxygen from the atmosphere into the blood and realease CO2 from blood outside. They are composed by part of the respiratory tract (bronchi, bronchioles) and millions of alveoli.

Alveoli are thin-walled air sacs covered with capillaries, where the gas exchange of CO2 and O2 takes place.

RESPIRATORY SYSTEM is formed by respiratory tract and lungs.

1.- nostrils 6.- trachea or windpipe 2.- nasal cavity 7.- bronchi 3.- mouth 8.- bronchioles 4.- pharynx 9.- alveoli 5.- larynx

CAPILLARIES

BRONCHIOLES ALVEOLI (SECTION)

ALVEOLI 3

USEFUL WORDS:

.- respiratory tract .- nostrils .- nasal cavity .- mouth .- pharynx 5.- larynx

.- lungs. .- trachea or windpipe .- bronchi .- bronchioles .- alveoli

O2

CO2

oxygenated blood Rich in O2

deoxygenated blood Rich in CO2

CO O2 2 CAPILLARY

2 C.E.I.P. SANTA ANA (Madridejos)

1

1.2.- MOVEMENTS OF LUNGS: There are two movements:

INSPIRATION or INHALATION AIR FLOWS IN

A.– Inspiration or inhalation (breathe in air). Lungs get air from the atmosphere, through the airways into the alveoli.

Inhalation begins with the contraction of diaphragm, and intercostal muscles that produce the expansion of the chest cavity.

Air comes in through nostrils, nasal cavity (where it gets warm and clean by mucus and hairs), larynx, trachea, bronchi, bronchioles to the alveoli.

MOVEMENTS OF LUNGS: .- Inspiration or inhalation, (breathe in air) .– Expiration or exhalation, (breath out air)

INTERCOSTAL MUSCLES CONTRACT

2 3

DIAPHRAGM CONTRACTS EXPIRATION or EXHALATION AIR FLOWS OUT

B.– Expiration or exhalation (breath out air). Lungs expel air from the alveoli to the atmosphere.

Exhalation begins with the relaxation of diaphragm, and intercostal muscles that produce that the space inside the chest cavity becomes smaller.

Air comes out from the alveoli, bronchioles...the rest of airways to the exterior.

INTERCOSTAL MUSCLES RELAX

4

5

RESPIRATION IN LUNGS

DIAPHRAGM RELAXES Air in Air out

CAPILLARIES

ALVEOLI

At the same time CO2 from blood (that comes from cells), passes through the capillaries to the alveoli, and later it is exhaled to the exterior.

oxygen in CO 2

CO2 out

1.3.– RESPIRATION IN LUNGS: In the pulmonary alveoli, oxygen from air passes through the capillaries into the blood (red blood cells).

O2

RED BLOOD CELLS

CAPILLARY

6 RESPIRATION IN CELLS Red blood cells with CO2, and waste products

Red blood cells with O2, nutrients...

Arterial end of capillary

O2

Venous end of capillary

Fluid

USEFUL WORDS:

CO2 Cells

1.4.– RESPIRATION IN CELLS: Oxygenated blood goes to every cell in the body. Oxygen is transported by red blood cells through the capillaries. Inside every cell, oxygen combines with nutrients from food to get energy and produces CO2.

Red blood cells remove CO2 (from every cell) and transport it to the lungs, where it will be expeled to the exterior.

7

.– inspiration or inhalation .– diaphragm .– expiration or exhalation .– intercostal muscles

3 C.E.I.P. SANTA ANA (Madridejos)

1.5.– PROTECT YOUR HEALTH: There are several problems with our respiratory system. Some viruses and microorganisms can come into our body (flu, ordinary cold…) producing infections and causing some problems. But there are also other reasons, like allergies, asthma, lung cancer…

A.– Infections: Through our airways, some microorganisms (bacterias, viruses…) can get into our body and affect our health.

If we breath through our nasal cavity, mucus and nasal hairs warm up, filter and clean the air.

But some microrganisms can produce illnesses like pneumonia, ordinary cold or the flu, and they are very contagious.

Flu Symptoms

B.– Allergies, asthma: There are some chronic diseases that affect the respiratory system.

Some products (pollen, animals fur…) produce reactions or allergies mainly in the respiratory tract (like runny nose, cough…)

1

Asthma is a disease that produce the inflamation of bronchi.

Bronchial tubes become tighter and thicker with mucus, and air gets into lungs with some difficulty.

Bronchial tube

C.– Other diseases: There are other important diseases like emphysema 2 that damages alveoli in the lungs, and breathing needs more effort.

Lung cancer is uncotrolled growth of abnormal cells.

These cells form tumors that interfere with the function D.– WHAT WE MUST DO TO PREVENT THESE of lungs.

PROBLEMS: The main cause of these diseases is smoking.

1.– Breathing through your nose will warm up, filter and clean the air, and will reduce partially some infection diseases.

2.– Ventilating the room, avoiding air pollution and products that cause allergic reactions are good pieces of advice for everybody and people with asthma or allergic problems.

3.– Don’t smoke. Smoking is the main cause for very dangerous problems, like emphysema, bronchitis and lung cancer.

People who smoke is killing themselves and tobacco also affects their children, family, friends… (passive smokers)

3

4.– Visit the doctor when you feel sick, you have problems to breath, or you have an infectious disease.

5.- Practice sports and do exercise regularly. They are the best way to feel good and stay healthy. You’ll improve you lung capacity, and you’ll breath better.

USEFUL WORDS:

.– pneumonia .– allergy .– lung cancer

.– ordinary cold .– asthma .– smoker

.– the flu .– emphysema

4 C.E.I.P. SANTA ANA (Madridejos)

2.– EXCRETION. Excretion is the process of removing waste products from the body.

Many systems do these actions: .– Digestive system removes faeces. .– Respiratory system removes Carbon dioxide.

But there are two systems specialized in removing toxic products: .– Urinary system that filters blood (kidneys, ureters…) .– Skin with millions of sweat glands.

EXCRETION is the process of removing waste products from the body. .– Urinary system: filters blood (kidneys…) .- Skin: produces sweat.

1

2.1.– URINARY SYSTEM. Urinary system filters blood to remove waste products from every cell in our body, and expel them in a liquid called urine.

It’s a tract with different organs.

A.– Components: A.1.– Two kidneys: Kidneys are two bean-shaped organs placed above the waist, at the back, near the spinal column.

There are two kidneys. They filter blood to extract waste products, return clean blood to the circulatory system and control the level of water in our body.

Blood is transported by a renal artery, and a renal vein. Inside the kidneys there are capillaries that cover millions of microscopic structures called nephrons, that filter blood.

They extract waste products and water and they form urine.

2

A.2.– Two ureters: The ureter is a tube that transports urine to the bladder.

There are two ureters, one from each kidney.

A.3.– Bladder: It’s a muscular bag that stores urine from kidneys.

It has got a muscle called sphincter that closes the bladder’s exit.

When the bladder is full, sphincter relaxes and urine goes out.

A.4.– Urethra: It’s a tube that connects bladder with the exterior, to expel the urine.

KIDNEY

3 RENAL ARTERY.

Blood with waste products

RENAL VEIN.

Clean blood URETER

Waste products (urine) to the bladder

URINARY SYSTEM: filters blood to extract waste products and controls the level of water.

Components: kidneys, ureters, bladder, urethra

NEPHRON

CAPILLARIES

B.– Process: The blood goes to the kidney by the renal artery. This artery becomes capillaries that are surrounding millions of microscopic structures called nephrons. Nephrons get waste products and some water to form urine, and the renal vein returns clean blood to the circulatory system.

Urine goes down through ureters to the bladder, where it is collected. When the bladder is full, urine is expeled through the urethra to the exterior.

USEFUL WORDS:

.– urinary tract .- bladder

Tubule to the Ureter

.– kidney .– sphincter

.– nephron .– urethra

.– ureter 4

5 C.E.I.P. SANTA ANA (Madridejos)

1

2.2– EXCRETION THROUGH SKIN. Our skin is the biggest organ in our body. It has millions of sweat glands that produce sweat. Sweat is a mixture of water, salts and waste products.

When we sweat: A.– We control our body temperature. When we do some exercise or it is too hot, we sweat and our body cools down.

B.– We filter blood. Sweat glands collect waste products and water from blood (that comes from the cells) and these waste products are expelled to the exterior through pores.

Sweat gland pore

Hair Epidermis

Dermis

Sweat gland

Sweat glands are surrounded by capillaries. Sweat glands filter blood from capillaries and expel water and waste products (sweat).

Capillaries Touch nerve ending

2

3

4

2.3.– PROTECT YOUR HEALTH: There are some problems related with excretion. The most common ones are:

5

A.– Urine infection: When some microorganisms (bacteria, fungi…) get into the urinary tract, can produce fever, pains…

B.– Stones in the kidneys: When kidneys filter blood, sometimes minerals and waste products can form sand or little stones that have to be expelled through ureters, bladder and urethra. They can produce a lot of pain, fever…

C.– Infections on skin, acne, spots, abscess…

Sometimes pores are blocked, so sweat and waste products can’t be expelled, and this problem can produce infections.

6

D.– WHAT WE MUST DO TO PREVENT THESE PROBLEMS: 1.– Drink at least two litres of water or liquids a day.

Water is very good for our health. It makes easier the blood filtration, and can disolve little stones in the kidneys.

It’s also good for infections in the urinary tract and skin.

Kidney stones

2.– To have a good hygiene: take a shower everyday.

Most of infections are caused by an inadequate hygiene. So pores can be blocked by dirty particles that provoque problems and diseases.

3.– Protect our skin.

If we protect our skin from weather conditions (protect it from the sun with a sunscreen), and hydrate it with hygiene products and creams, our skin will be clean and healthy.

4.– Go to the doctor if you have some problems.

We need to go to the doctor when we have some problems, we have a serious infection on our skin, or a pain produced by our urinary tract.

We sometimes need to have antibiotics to control the disease.

ACNE VULGARIS

7

USEFUL WORDS:

.– sweat glands .– kidney stone

8

.– pore .– acne