OKLAHOMA 3D
HS Biology STEMscopedia
Table of Contents
Biomolecules
Think about It
1. Think about the phrase “You are what you eat.” Describe what this means to you.
STEMscopedia
We Are All Made of Stardust
What Makes Us Different from the Stars?
STEMscopedia
What’s in a Biomolecule?
2. Compare the structures of andmonosaccharides
Whichpolysaccharides. do you think would be easiest to digest and why?
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Carbohydrates
Simple Carbohydrates
Complex Carbohydrates
Monosaccharide (glucose)
Disaccharide (sucrose)
Polysaccharide
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3.Look at the given lipid. How many chemical bonds do you see? How is the structure of this lipid related to its role as a source of long-term energy?
Lipids
LIPID
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Nucleic Acids
4.Do you notice any patterns within the given DNA molecule? How could these patterns form the genetic code?
STEMscopedia
5. Look at the given image and think about what you just read. The proteins in the table serve very different roles in our bodies. How are proteins able to serve so many different functions?
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Proteins
Type of Protein Shape Examples of This Type of Protein
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Amino Acid Reactions
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Enzymes
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6. What do you notice about the shape of each enzyme and its substrate(s)?
Scientists in the Spotlight: Population Health Innovation Lab
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The Big Picture
Are we really what we eat?
Connect It
7.How do your cells rely on the biomolecules that are present in these food groups?
Summarize It
Prokaryotic and Eukaryotic Cells
Imagine It
1. How is cellular evolution similar to the development of human civilization?
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Discovery of the Cell
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Cell Theory
Robert Hooke
Cell Theory Time Line
Antonie van Leeuwenhoek Cell TheoryModern Cell Theory Additions
iscvers cells hile ling at cr in earl icrsce iscvers living cell acteria
All living things are ade cells. he cell is the asic nit lie. All cells ce r reeisting cells. etalis and hereditar transer are celllar rcesses cn t all cells.
21st Century
2. How does cell theory explain the origin of new cells?
Prokaryotes and Eukaryotes
rokaryoti Cell ateria
ukaryoti Cell rotists uni Animals lants
mooth endolasmi retiulum Ribosomes
Rouh endolasmi retiulum
mooth endolasmi retiulum
laellum
Casule
Lysosome
Chromatin
Mirotubules
Centriole
Ribosomes
Ribosomes
Cytolasmi
laellum
3. Why were archaea some of the last organisms to bediscovered?
Nucleus
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Eukaryotic Cell Organelles
Mitochondria
itchndrin “Cellville”
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Endoplasmic Reticulum and Ribosomes
Golgi Body
Cytoplasm
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4. How do the ER and Golgi body work together in a cell?
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Special Organelles
Chloroplasts
Vacuoles and the Cell Wall
5. Why would a cell a plant cell?
Chlorolast
Chloroplasts
Cell wall
Vacuole
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Plant and Animal Cell Differences
Symbiogenesis
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Endosymbiotic Theory
Evolution
6.
Why do you think there are more prokaryotes than eukaryotes?
Ancestral prokaryotes
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Evolution of nucleus
Evolution of mitochondria from aerobic endosymbionts
Evolution of chloroplasts from photosynthetic endosymbionts
DNA
Nuclear envelope
The Big Picture
Connect It
7. How does comparing prokaryotic and eukaryotic cells help us understand how life-formscomplexhave evolved from simpler origins?
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Summarize It
Homeostasis
Think about It
1. How does sweating help maintain homeostasis?
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Cellular Homeostasis
2. What would happen if the cell membrane were notpermeable?selectively
Passive Cellular Transport
3. What do you think happens to a cell if too much water enters the cell or if too much water leaves the cell?
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4. What are the differences between diffusion and facilitated diffusion?
Active
Cellular Transport
5. What would be some consequences of the sodium-potassium pump not properly?working
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Scientists in the Spotlight: Banting, Best, Collip, and Macleod
The Big Picture
Connect It
Why do we sweat?
6. What are other ways in which our bodies respond to maintain homeostasis?
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Summarize It
Diseases
Think about It
1. What could happen if a infectionbacterial is untreated?left
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What Is a Virus?
Capsid
Virus
Spikes
DNA or RNA
A nonliving particle dependent on host cells for replication of genetic material
2. What are some characteristics of living organisms that are not exhibited by viruses?
Where Did Viruses Come From?
3. What is the smallest organism that you have ever seen with a glass?magnifying Can you see cells with a magnifying glass?
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The Lytic and Lysogenic Cycles
Lyti Cyle
irs A irs article
iral rerdctin reslting in the lsis slitting the hst cell and the rdctin re virs articles anactred the hst cell C
4. How are the lytic and cycleslysogenicsimilar? How are different?they
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Viruses Compared with Cells
5. How is viral reproduction similar to cellular reproduction? How is it different?
S
Period of cell growth before the DNA is duplicated
Period when the DNA is duplicated (that is, when chromosomes are duplicated) (interphase begins in daughter cells)
Cytoplasm divided
(interphase ends inparent cells)
G2
Period after DNA is duplicated; cell prepares for division
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iruses
nliving eed a hst cell t rerdce rganelles aller than acteria
imilarities ateria
ntain genetic aterial Living a cntain rganelles igger than virses ntain rises
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Cancer Cells
6. What makes cancer different from other diseases?
Other Disease Types
7. How are disease causes alike? How are they different?
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Scientists in the Spotlight: Dr. William G. Kaelin, Jr.
The Big Picture
Connect It
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Summarize It
Cell Cycle and Specialization
Think about It
1. Imagine a humpback whale side-by-side with an anchovy. Which organism has larger cells? Explain why you think so.
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Starting as a Single Cell
2. When an organism grows, do its cells grow, or does it produce more cells? Name and describe two situations in which a cell undergoes mitosis.
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How Does Cell Division Work?
Eukaryotic Cell Cycle
1 2
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Cell Cyle
Mitosis
Telohase and Cytokinesis
r
envele ring leavage rr clels ring
3. Why is it cell that doesn’t a checkpoint to undergo programmed cell death?
Centromere
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Advanced Topics
Binary Fission vs. Mitotic Cell Division
Prokaryotic Cell Cycle: Binary Fission
Chromosome
Cell
DNA replication
Segregation
Cytokinesis
How Is DNA Duplicated?
4. How does basecomplementary pairing help ensure that an is made during DNA replication?
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5. All the cells in a multicellular organism contain exactly the same DNA. How can cells with the same produce extremely
6. How would you expect the genes expressed in a lung expressed in a skin cell? How would the DNA in that lung cell compare to the DNA in the skin cell?
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Scientists in the Spotlight: Hilde Mangold
The Big Picture
Connect It
How are the cells in a whale the same as the cells in an anchovy? How are they different?
7. Besides lung and gill cells, what other specialized cell types between a whale (a mammal) and an What specialized cell in both the whale and the anchovy?
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Summarize It
Cellular Respiration and Photosynthesis
Think about It
1. How do our bodies extract energy from the food that we eat? Where does that energy come from?
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Advanced Topics
Formula Representations of Molecules and Compounds
Molecular Formulas Structural Formulas
Energy and Its Forms
Where Does Life on Earth Get Its Energy?
How do plants get energy?
How do animals get energy?
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How does energy change forms?
2. List two cell activities that might require energy from ATP.
What Is Photosynthesis?
3. Compare the number of carbon atoms in a molecule of carbon dioxide (a reactant) and a molecule of glucose (a product). Is photosynthesis building something up or tearingdown?something
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What are the light-dependent reactions?
hlrlasts htsnthesis rganelles
4. What do light-dependentthe reactions send over to the reactions?independentlightWhat do thereactionslight-independent send back to the light- dependent reactions?
in thlaid stacs
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What are the light-independent reactions?
Lightdeendent reactins in thlaid
Lightindeendent reactins in stra
Calvin yle
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What Is Cellular Respiration?
Inner erane
ristae atri
Intererane sace
itchndrin Inner trctre
How does cellular respiration start?
Glycolysis:
First Step of Cellular Respiration
Converts
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What is the Krebs cycle?
Acetyl-CoA contains a four-carbon compound, forming a six-carbon compound.
Krebs Cycle:
Second Step of Cellular Respiration
The new four-carbon compound is converted to the four-carbon compound that began the cycle.
CO2 is released from the six-carbon compound, leaving a five-carbon compound.
CO2 is released from the five-carbon compound, leaving a four-carbon compound.
The four-carbon compound is converted to a new four-carbon compound.
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What happens during the electron transport chain?
Step 3 Electron Transport Chain (Aerobic Respiration)
Intermembrane space
Mitochondrial matrix
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Cellular Resiration
letrons arried via AH
lyolysis
luose yruvate
Cytosol
Mitohondrion
rebs yle
letrons arried via AH and AH2
letron transort hain and oidative hoshorylation
2 net 232
substratelevel hoshorylation
substratelevel hoshorylation
substratelevel hoshorylation
5. Consider the three steps of cellular respiration. Which step is the Explain why the electron transport in producing ATP.
Aerobic versus Anaerobic Respiration
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Lactic Acid Fermentation
C16H12O6 2C3H6O3 + 2 ATP
Alcohol Fermentation
C16H12O6 2C2H5OH + 2CO2 + 2 ATP
Photosynthesis and Cellular Respiration
How is energy transferred in each process?
How is matter transferred in each process?
6. How would the transfer of energy be affected if there were fewer producers? Explain your prediction.
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Scientists in the Spotlight: Amanda Cavanagh
7. Why are producers the base of the pyramid? How do other living organisms depend on producers for energy?
The Big Picture Connect It
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Summarize It
Plant Structures
Think about It
1. If plants allow animals of greater complexity to thrive, then what would happen if plants begin to die off on Earth?
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Plants
Plant Kingdom
AlgaeLand Plants (specialized reproductive parts)
Nonvascular
Green algae
Mosses, liverworts, hornworts
Vascular (higher plants)
SporesSeeds
Ferns
Gymnosperms (seeds in cones)
Conifers, such as pine trees
Angiosperms (seeds in flowers)
MonocotsDicots
Flowering bulbs, grasses, etc.
Flowering plants, herbs, shrubs, trees
Green Algae
Nonvascular Plants
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Vascular Plants
2. How is the vascular system in plants like the circulatory system in animals?
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Gymnosperms
3. Why are gymnospermsevergreens?called
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Leaves
Roots
4. Why do plants invest in scents and brightlypetals?colored
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Angiosperm Reproduction
Stigma Style
Ovary
Carpel
Pistil Ovule
Petal
Petal
Anther Stamen Filament
Sepal
Sepal
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Monocots Dicots
Seed with one cotyledon
Seed with two cotyledons
Flower parts in threes
Flower parts in fours or fives
Leaf veins in parallel lines
Leaf veins branching
Pollen grains with one pore
Pollen grains with three pores
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Plant Cell Types
Parenchyma tissueCollenchyma tissueSclerenchyma tissue
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Roots, Stems, and Leaves
Roots
Stems
Potatoes are edible underground stems.
Celery stalks are edible stems.
Stems move water and nutrients to the rest of the plant.
Asparagus are edible stems.
Stems on trees are called trunks and branches.
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Leaves
The small openings on the undersides of leaves are called stomata.
The small openings on the of are stomata.
Hormones and Tropisms
Auxin Hormones’ Response to Environment Clues
5. Why is it important for plants to be able to respond to stimuli?
STEMscopedia
6. Are carnivorous plants autotrophs or heterotrophs? Explain.
7. How do defenses from predators in plants differ from those in animals?
STEMscopedia
Scientists in the Spotlight: Norman Borlaug
The Big Picture
Connect It
8. How do plants’ structures perform the functions that help them survive?
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Summarize It
Body Systems
Think about It
an d rgan stes
1. What are the levels of organization in biology that create the human body?
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Human Immune System
HUMAN IMMUNE SYSTEM
NONSPECIFIC DEFENSE MECHANISMS
FIRST LINE OF DEFENSE
Skin
Mucous membranes
Secretions of skin and mucous membranes
SECOND LINE OF DEFENSE
Phagocytic white blood cells
Antimicrobial proteins
The inflammatory response
THIRD LINE OF DEFENSE SPECIFIC DEFENSE MECHANISMS (IMMUNE SYSTEM)
Lymphocytes
Antibodies
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2. What is the immune system’s main function?
3. What is one difference between a vaccine and antibiotics?
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Cardiovascular System
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4. What are the parts of the cardiovascular system?
5. Why is blood circulation important?
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The Human Brain
Advanced Topics
6. What role does the brain play in the body?
7. What is the largest part of the brain?
8. What are the parts of the brain stem?
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Reproductive System
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9. What is the purpose of the reproductive system?
First Trimester: 0–12 Weeks
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Human Development
Second Trimester: 13–27 Weeks
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Third Trimester: 28–40 Weeks
10. When does implantation occur?
11. If you were a doctor, what features would you notice on a fetus in the second trimester?
Scientists in the Spotlight: Dr. Daniel Hale Williams
The Big Picture
STEMscopedia
Connect It
What are the levels of organization that make up human beings?
12. What are the levels of organization that make up multicellular organisms?
Summarize It
Think about It
Th M f h le ul L DNA: The Molecule of Life ife Life
1. How is the structure of DNA related to the genetic code?
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What is DNA, and where is it found?
2. How does DNA differ from organism to organism if we all have the same four letters?
DNA Shape and Structure
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DNA’s Double Helix
Sugar molecules
Weak hydrogen bonds
Phosphate molecules
Nitrogenous bases
Sugar-phosphate backbone
The Ladder Model
Genetic Code: The Key to Our Traits
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DNA vs. RNA
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DNA Replication
Meselson and Stahl Experiment
3. How did scientists determine that DNA is replicated by the semiconservative model?
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Scientists in the Spotlight: RNA World Hypothesis
Did DNA or RNA come first?
4. How did determinescientists that DNA is material?hereditary
Discovering that DNA Contains Genetic Information
Mouse lives
Rouh strain nonvirulent mooth strain virulent
Heatkilled smooth strain
Rouh strain and heatkilled smooth strain
Mouse lives Mouse diesMouse dies
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Bacteriophages
After centrifugation no sulfur in cells
After centrifugation phosphorus in cells
cell
1. Infection
2. Blending
3. Centrifugation
sulfur labeled protein capsule (red) cell phosphorus labeled DNA (green)
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Gene Expression
5. How are transcription and translation different?
STEMscopedia
6. Outline the steps of DNA coding for a protein.
The Big Picture
7. How does DNA specify the traits of an organism?
STEMscopedia
Summarize It
Gene Expression
Think about It
1. How do you think liver and brain cells can develop different structures if they contain the same DNA?
STEMscopedia
Organization and Types of DNA
Is all DNA equally important?
2. How might cellular (enzymes)machinery work to of a chromosome to gene?
STEMscopedia
Gene Expression
Information Flow in a Cell
3. What do you notice about the locations of DNA and mRNA in the diagram of expression?gene
Transcription:
Information Transfer: DNA to mRNA
RA rs ase airs ith ncletides in A.
hen RA lerase transcries the A ganine airs ith ctsine and adenine A airs ith racil .
Why mRNA?
4. Do DNA and RNA follow the same complementary rulesbase-pairing as when the pairing is between two DNAExplain.nucleotides?
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Translation
Building Proteins with mRNA
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5. Which amino acids have more than one codon? Which amino acids are coded for by only a single codon?
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6. What happens to the tRNA in the third position after the ribosome moves to a new mRNA codon?
Anticodon
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Amino Acid Sequence in Polypeptides
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Changes to the DNA Sequence
7. Why might a mutation that changes one or two nucleotides have a larger effect than a mutation that affects three, six, or nucleotides?nine
Cell Differentiation
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Scientists in the Spotlight: Dr. Benyam Kinde
The Big Picture
8. How does gene expression determine the specialized shape and function of a cell?
STEMscopedia
Summarize It
DNA Technology
Talk about It
1. What do you think is the most invention of all time? How did this invention help scientists make future discoveries?
The History of Genetic Technology
2. List the order of major advances in genetic technology of the DNA molecule in the 1860s to the development of DNAtechnology.sequencing
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Uses of the DNA Sequence
3. List two questions that you can answer by using a DNA sequence.
Studying DNA
4. Based on the DNA gel image, which samples came from the same individual? How do you know?
riginal A seence denatred and aliied ith
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How DNA Is Sequenced
itre ds and lrescent dds lrescentl laeled ligncletides
5. How is DNA sequencing similar to DNA replication? How is it different?
Genetic Engineering and DNA Technology
6. How could plants farmers money? How might the human genome be healthcare costs?
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Advanced Topics
Scientists in the Spotlight: Dr. Emmanuelle Charpentier and Dr. Jennifer Doudna
The Big Picture
Connect It
Advances in technology depend on curiosity and innovation.
7. Which technique(s) do you think are the most important for advancing our understanding of DNA? Which do you think holds the most potential for humankind’simproving quality of life?
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Summarize It
Meiosis and Reproduction
You are half and half!
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Think about It
1. If half of a person’s DNA comes from each of their biological parents, why aren’t all biologicalidentical?siblings
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Reproduction
2. What kind of organisms go through meiosis and sexual reproduction?
3. Sexual reproduction is a longer process than asexual reproduction. Why do you think that is?
Human Chromosomes total o 6
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Meiosis
InterphaseMeiosis I Daughter nuclei Daughter nuclei II Meiosis II
Homologous chromosomes
The Phases of Meiosis (PMAT)
Meiosis I: Reduction, Division, Crossing-Over, and Independent Assortment
Crossing-Over
Synapsis: pairing of homologous chromosomes
Crossing-over
The exchange of genetic material between homologous chromosomes during meiosis; contributes to genetic variation
ndeendent Assortment
Random seletion o hromosomes durin meiosis to orm ametes
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Meiosis II: Four Haploid Cells Are Formed
Somatic cell
Diploid (2n)
Egg and sperm
Haploid (1n)
4. Why do you think that crossing-over and assortmentindependent are important processes in sex cells?
Gametes
Zygote
Sexual Reproduction and
Genetic Diversity
5. Is there another way of geneticintroducing variation besides crossing-over andassortment?independent
Selfish Gene Theory
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Scientists in the Spotlight
Crossing-over
The Big Picture
STEMscopedia
Summarize It
Genetics and
Inheritance
Think about It
1. How do you think we can predict what traits an offspring might inherit?
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Mendelian Genetics and Inheritance
Inheritance of Mendelian Traits
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Parental generation (P)
100%
All plants have purple flowers.
First generation (F1)
75%
Three of every four plants have purple flowers.
Second generation (F2)
Mendel’s Laws of Genetics
The Law of Segregation
The Law of Independent Assortment
The Law of Dominance
2. How did experimentsMendel’s help scientists learn about patterns of inheritance?
Parent 2
Parent 1
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Punnett Squares
PPP P PP P is purple and dominant. P P = Purple = Purple = White is white and recessive.
3. What is the relationshipgenotypebetween and phenotype for a given trait?
Monohybrid CrossDihybrid Cross
One phenotype is predicted.Two phenotypes are predicted.
4. How could you use a Punnett square to determine the genotype of an unknownorganism?parent
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Non-Mendelian Inheritance
Types of Non-Mendelian Inheritance
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Scientists in the Spotlight: Dr. Mary-Claire King
The Big Picture
Connect It
How can we predict what traits an offspring might inherit?
Generation I (parents) Generation II (children) Generation III (grandchildren)
5. How can a pedigree chart help predict offspringwhether might inherit a sex-linked genetic disease?
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Summarize It
Classification of Organisms
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Think about It
1. How could we organize the organisms in a pond based on their similarities and differences?
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The Taxonomic System
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The Three Domains
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The Six Kingdoms
Anialia
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2. Describe the three ways that organisms are different kingdoms. Use new vocabulary terms in explanation.your
Characteristics of Domains and Kingdoms
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3. How are members of kingdom Archaea and Bacteriakingdomdifferent?
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4. How would energy supplies in ecosystems be affected if there were no fungi or animals?
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agish erch
alaander Liard
igen se hi
eathers r and aar glands
las r nails Lngs as
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5. How do you determine which organisms are most closely related using a cladogram?
STEMscopedia
Scientists in the Spotlight:
Roseli Ocampo-Friedmann, Microbiologist and Botanist
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The Big Picture
Connect It
How can the organisms in a pond be classified?
Evidence for Evolution
Think about It
1. What is exampleanother of technological evolution that you are familiarwith?
STEMscopedia
Evolution
2. What evidence do you think scientists use to support the theory of evolution?
The Fossil Record
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3. What do you think is happening when a new species suddenly appears in the strata?
ssil reains Cynognathus a riassic land retile ariatel lng.
Biogeography
ssil evidence the riassic land retile Lystrosaurus
ssil reains the reshater retile Mesosaurus
4. How can scientists use the tectonic plate theory and the fossil record together to provide evidence of evolution?
ssils the ern Glossopteris nd in all the sthern cntinents sh that the ere nce ined.
ARIA
IIA
ARIA
AARIA
ARALIA
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Anatomical Evidence for Evolution
5. What is the difference betweenstructureshomologous and analogousstructures?
Developmental Evidence for Evolution
6.
Hominid Evolution
7. What are some characteristics used to classify hominids on the evolutionary timeline?
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Scientists in the Spotlight: Charles Darwin
How has technology evolved?
The Big Picture
Connect It
8. How is the evolution of technology similar to the evolution of biology?
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Summarize It
Mechanisms of Natural Selection
Think about It
1. How on Earth did giraffes end up with the longest necks among all animals?
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Natural Selection
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The Mechanism of Natural Selection
2. Are we still evolving by selection?natural
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Where the Variation Comes From
3. How can a population with a small gene pool promote more variation?
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DNA Mutation
4. Does natural selection get rid of mutations or variations?
Sexual Reproduction
Gene Flow
Genetic Drift
5. How can isolation start new species?
Genetic Drift Dramatic in Small Populations
The net effect of genetic drift on a small population’s gene pool can be rapid evolution. The red trait dramatically increases in frequency from generation to generation.
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Microevolution and Macroevolution
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Microevolution
Natural Selection and Polygenic Traits
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Directional Natural Selection
Percentage of population
Members at one end of the distribution curve have a higher fitness than those in the middle or at the other end of the curve.
Disruptive Natural Selection
Selection for extreme trait values; often results in two different values becoming most common, with selection against the average value
Bill depth
Scientists in the Spotlight: Darwin and Mendel
Gregor Mendel discovered rules of inheritance using pea plants.
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Summarize It
Results of Evolution
Think about It
1. What changes to the gene pool are necessary to create different dog breeds?
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Natural Selection
Genetic recombination: the process by which new combinations of alleles that are not found in the parents are produced in offspring
CORRECT
Nonrandom survival
Generation 1
Reproduction and undirected mutation
Nonrandom survival
Reproduction and undirected mutation
Generation 2
Many generations of mutation and natural selection
Generation 3Generation N
INCORRECT
Generation 1a
Change of individual organisms
Generation 1b
Reproduction and mutations in response to need
Generation 2
ene l echange alleles eteen latins
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Gene Flow
Genetic Drift
A type of genetic drift in which the population size is greatly reduced due to natural disaster, predation, or habitat loss
Bottleneck Effect
2. What is a species?
Speciation
eciatin event
Ancestral lineage
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Prezygotic Barriers
3. When a donkey and a horse mate, the offspring is a mule. Is a mule a new species?
Postzygotic Barriers
A clade
clade t a clade t a clade
4. Explain how natural selection and gradualism go hand in hand.
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How to Keep New Species Separate
Allopatric Speciation Sympatric Speciation
5. How does polyploidy create genetic diversity?
Advanced Topics Biological Diversity
Scientists in the Spotlight: Carl Linnaeus
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The Big Picture
Invasive
Harvesting (hunting/gathering)
Accidental
Persecution Pollution
Natural
Changes
Species and Ecological Interactions
Connect It
Intrinsic
6.
Summarize It
Ecological Relationships
Think about It
1. How do organisms that live in the same ecosystem affect each other?
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Types of Interactions in Ecosystems
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2. How do interactions between organisms within an ecosystem ecosystem’s stability?
Matter and Energy Flow in Ecosystems
Liard
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3.
What are the effects on an ecological system if many consumerssecondary die?
4. What happens when an energy resource in an ecosystemdepleted?becomes
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Carrying Capacity and Limiting Factors
5. What factors might cause carrying capacity to change?
Chemical Cycles in Ecosystems
6. What are the consequences if the nitrogen cycle or the carbon cycle is disrupted?
Scientists in the Spotlight: Heinrich Anton de Bary
Potato Blight Pathogen Ruined Irish Potato Crop 1845–1852
The fungus Phytophthora infestans (blight) caused the Irish Potato Famine.
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The Big Picture
Connect It
How do interactions between organisms affect ecosystem stability?
7. Why are interactions in an ecosystem important to the survival of a species?
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Summarize It
Lion Hyena
Cheetah Giraffe
Acacia tree
Dung beetleThe Sun Grass
Baboon
Termites
Zebra
Changing Biodiversity
Think about It
1. Why would having a larger variety of organisms lead to greater stability in anecosystem?
What Is Biodiversity?
2. Why is biodiversity important to humans?
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Environmental Changes that Affect Ecosystem Biodiversity
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3. Imagine a river where an oil spill happens. What are all the processes in an ecosystem that could be affected by that spill?
SECONDARY SUCCESSION
rimary uession ioneer eies
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eondary uession ioneer eies
Mosses
Lihens
ildlowers
rasses
STEMscopedia
Organisms’ Interactions with Biotic and Abiotic Factors
4. Why is it so important to analyze changes in an ecosystem over a long period of time?
STEMscopedia
The Big Picture
Connect It
How do invasive species affect an ecosystem’s stability?
5. How does the introduction of non-native species affect an ecosystem?
Summarize It
Carbon and Nitrogen Cycles
Think about It
1. How are the carbon and nitrogen cycles similar to our bodies’ forsugar?need
STEMscopedia
Carbon and Nitrogen Cycles
Biogeochemical Cycles
STEMscopedia
Carbon Cycle
reenhse ect lecles ater arn diide ethane ne itrs ide
2. What do you think would happen to Earth’s temperature greenhousegases?without
lar radiatin ers the cliate sste.
e slar radiatin is relected arth and the atshere.
The reenhouse et
e the inrared radiatin asses thrgh the atshere t st is asred and reeitted in all directins greenhse gas lecles and clds. he eect this is t ar arths srace and the ler atshere.
At hal the slar radiatin is asred arths srace and ars it.
Inrared radiatin is eitted r arths srace.
STEMscopedia
Photosynthesis
Carbon Sources and Sinks
Biological Carbon Cycle
nerg ls and atter Is cled thrgh htsnthesis and elllar Resiratin
HTTH nery stored
nery released CLLLAR RRAT
STEMscopedia
Geological Carbon Cycle
Major Carbon Reservoirs (in Gigatons)
Vegetation: 610
Soils: 1,560
Atmosphere: 600 (preindustrial)
Ocean mixed layer: 1,000
Sediments and rocks: 66,000,000
Deep ocean: 38,000
3. How do carbon sinks help reduce the amount of carbon in the atmosphere?
STEMscopedia
Human Impact on the Carbon Cycle
4. How do decomposers contribute to the carbon cycle?
STEMscopedia
Nitrogen Cycle
5. What would happen to plants if bacteria weren’t able
STEMscopedia
STEMscopedia
Human Impact on the Nitrogen Cycle
Algal Bloom: Disruption of the Nitrogen Cycle
6. How do humans disrupt the nitrogen cycle?
STEMscopedia
Water Cycle
STEMscopedia
7. How does water change states as it travels through the water cycle?
Scientists in the Spotlight: James Hansen
STEMscopedia
The Big Picture
Connect It
Why are the carbon and nitrogen cycles so essential to all living organisms?
8. Why are the carbon and nitrogen cycles so essential to all living organisms?
Summarize It
Water and Life
Think about It
1. Why is water’s ability to hold itself together important?
STEMscopedia
Water and Life
2. Why is water a polar molecule?
Cohesive Behavior
STEMscopedia
Unique Properties of Water
High Surface Tension
High Boiling Point and High Freezing Point
High Specific Heat
STEMscopedia
Water Expanding upon Freezing
Solvent Properties
3. What are the unique properties of water?
STEMscopedia
Life in Aquatic Systems
Chemical Factors
STEMscopedia
Geographic Factors
4. The distribution of life in aquatic ecosystems is determined by what factors?
Scientists in the Spotlight: Luna Leopold, Hydrologist and Geomorphologist
STEMscopedia
The Big Picture
Connect It
How do the properties of water affect chemical and biological systems?
5. How do the unique chemical and physical properties of water make life on Earth possible?
Summarize It
Renewable Energy
Think about It
1. Where does the energy we use every comefrom?day
What Are Energy Sources?
What Is Nonrenewable Energy?
STEMscopedia
STEMscopedia
Natural Gas
2. What are some ways that fossil fuels are used besideselectricity?generating
What Is Renewable Energy?
STEMscopedia
Hydroelectric
STEMscopedia
Geothermal
3. Which renewable energy source do you think has the most potential for use in the UnitedWhy?States?
STEMscopedia
Nonrenewable Energy
4. Choose one of the disadvantages of usingsourcesnonrenewable and describe a way to help lessen the negative effect(s).
Renewable Energy
5. Explain at least one way that renewable energy sources have been used for centuries, before the consumptionaccelerated of fossil fuels.
STEMscopedia
Other Resources
Water and Groundwater
Soil
Forests and Wildlife
STEMscopedia
STEMscopedia
6. How can a aresourcerenewablebecome nonrenewable resource?
Individual Sustainability
reduce reuse recycle
STEMscopedia
STEMscopedia
7. Why is it important to know which components of a resource need to be monitored?
Advanced Topics
Large-Scale Environmental Impacts
Society and the Energy Debate
Scientists in the Spotlight: Union of Concerned Scientists
The Big Picture Connect It
8. How technologyimprovementsmightto improve the use of andnonrenewablebothenergyrenewable sources?
STEMscopedia
Summarize It
GLOSSARY OF TERMS
abiotic factorsamino acid sequence
abiotic factors: not living, or produced by nonliving things
activation energy: energy needed for a reaction to occur
active transport: the movement of a substance across a membrane that requires the use of energy; movement is against the concentration gradient
adaptation: a process by which the heritable characteristics of a population change such that the organisms in the population become better able to survive and reproduce in their environment
adenine: a purine base that pairs with thymine in DNA and uracil in RNA
adenosine triphosphate (ATP): the primary molecule used by cells to store chemical energy for use in cellular processes
aerobic cellular respiration: the process by which cells use oxygen and the chemical energy stored in nutrients to make ATP
agriculture: the science and business of cultivating soil, growing crops, and raising livestock
alcohol fermentation: a biological process that produces ethanol and carbon dioxide by the conversion of sugars into cellular energy in the absence of oxygen; generally used by yeast and bacteria
allele: a single, distinct version of a gene
amino acid: a molecule containing an amine group, a carboxylic acid group, and a side chain that is specific to each type of amino acid
amino acid sequence: A string of amino acids in a specific order to produce the desired protein molecule
GLOSSARY OF TERMS
ammonification: the process by which bacteria convert organic nitrogen into inorganic ammonium
anaerobic respiration: the process by which cells convert the chemical energy stored in nutrients into ATP, using an electron transport chain with a final electron acceptor other than oxygen
analogous structures: various structures in different species that have the same appearance, structure, or function but have evolved separately and do not share a common ancestor
angiosperm: a type of plant that produces flowers
anther: the portion of the male reproductive structure of a flowering plant that contains pollen (the male gamete)
antibiotics: specially designed chemical compounds that kill and prevent the growth of bacteria
atom: the smallest unit of an element that has all of the properties of that element; contains a nucleus within a surrounding electron cloud
anaphase: the phase of mitosis in which spindle fibers begin to shorten, separating the sister chromatids and pulling them to opposite ends of the cell
ancestry: the lineage of successive parents and offspring that leads to an organism or species
autotroph: an organism that obtains its energy from an abiotic source, such as sunlight or inorganic chemicals
bacteria: a prokaryotic organism that is a member of the domain Bacteria
GLOSSARY OF TERMS
base pairblood pressure
base pair: a pair of nucleotides found in one or more nucleic acid strands that are attracted together through hydrogen bonding
biodiversity: the sum of the different forms of living things in a given area or population
biogeochemical cycle: pathways for the transport and transformation of matter within four categorical areas that make up planet Earth (the biosphere, hydrosphere, lithosphere, and atmosphere)
biogeography: the study of the past and present geographical distribution of species
biomolecule: a molecule that is produced by living things
biosphere: the sum of all the life on Earth
biotic factors: living, or produced by living things
blastocyst: a structure formed in the early development of mammals; possesses an inner cell mass (ICM) that subsequently forms the embryo blood: a fluid that carries gases, nutrients, and wastes through the body; made of plasma, red blood cells, white blood cells, and platelets
blood cell: a specialized cell that carries oxygen through the bloodstream
blood circulation: the flow of blood throughout the body; arteries carry blood away from the heart; veins carry blood back to the heart; capillaries are tiny blood vessels that allow an exchange of nutrients and waste between blood and body cells.
blood pressure: the pressure of the blood in the circulatory system; closely related to the force and rate of the heartbeat
GLOSSARY OF TERMS
blood vesselscell cycle
blood vessels: tubes that hold blood; includes three types: arteries, capillaries, and veins
bottleneck effect: a reduction of the size of a population to a single or a few individuals, resulting in loss of genetic variation
carbohydrate: a biomolecule that contains hydrogen, carbon, and oxygen in a 1:2:1 ratio and that is used as a primary energy source and structural support
carbon cycle: the continuous movement of carbon in and among the abiotic environment and living things
carbon footprint: the tons of carbon dioxide and other greenhouse gases a person or organization produces each year from using fossil fuels
carbon sink: A reservoir, either natural or artificial, that absorbs more carbon than it releases
cardiovascular system: a system that circulates blood through the body, supplies oxygen and nutrients, and removes waste; it includes the heart, arteries, and veins; red color symbolizes veins and blue color arteries. Your blood is always a red color as it circulates through your body. This system is also known as the circulatory system.
carnivores: animals that eat other animals
carrying capacity: the maximum number of organisms an ecosystem can support
catalyst: a substance that speeds up or promotes a chemical reaction without being chemically changed by the reaction
cell: the basic structural unit of all living organisms
cell cycle: the process by which cells grow and divide to produce more cells
GLOSSARY OF TERMS
cell membranecladogram
cell membrane: a lipid bilayer that surrounds the cytoplasm of a cell, separating the inside of the cell from the environment and controlling what enters and leaves the cell
cerebrum: the upper part of the brain, which contains the cerebral cortex, hippocampus, basal ganglia, and olfactory bulb and is responsible for all voluntary actions
cell theory: a theory that states the following: all life is made up of cells, cells are the fundamental unit of life, and all cells come from preexisting cells
cell wall: a tough, protective barrier that surrounds the outer membrane of some types of cells
cellular respiration: the process by which cells convert chemical energy stored in various compounds, such as sugars, into useful energy for cellular processes; may be aerobic or anaerobic
cervix: the lower part of the uterus in mammalian reproductive systems
chloroplast: the organelle where photosynthesis occurs in plant cells
chromatin: DNA wrapped tightly around small bundles of protein, reducing the space the DNA takes up in the cell
chromosome: a structure made of DNA that contains the genetic information in the form of genes needed to carry out cell functions
cellular transport: the movement of materials across cell membranes
cladogram: a branching diagram representing a hypothesis about the evolutionary descent of groups of organisms from a common ancestor
GLOSSARY OF TERMS
climate change: a long-term change in the temperature range and related environmental variables for regions of Earth
climax community: the dynamically stable ecological community representing the final stage of ecological succession
codon: a sequence of three nucleotides in mRNA that encodes a specific amino acid or a signal to stop translation
cohesion: the action of molecules sticking together
commensalism: a symbiotic relationship where one organism benefits and the other organism is neither harmed nor helped
comparative embryology: the study of the similarities and differences in the stages of embryonic development among different species
competition: a condition that occurs when two or more organisms compete for the same resources within an ecological community complementary base pairing: when a DNA molecule’s nitrogenous bases align with each other concentration gradient: the process in which particles move through a solution or gas from an area with a higher number of particles to an area with a lower number of particles
condensation: the process by which a sample of matter changes from a gaseous state to a liquid state
consumer: an organism that must consume other organisms for nutrients
GLOSSARY OF TERMS
crossing-over differentiation
crossing-over: the exchange of genetic material between homologous chromosomes during meiosis; contributes to genetic variation
cytokinesis: the phase of the cell cycle in which the plasma membrane begins to cleave the cytoplasm into two separate but identical cells
decomposition: the process of breaking down a substance into its smaller components of organic matter; the process of decaying
deforestation: removal of a forest or stand of trees, which are then used for nonforest purposes
cytoplasm: the jellylike material inside the outer membrane of a cell that holds the nucleus, organelles, and other components of the cell
cytosine: a pyrimidine base that pairs with guanine
decomposers: organisms such as bacteria and fungi that break down the remains of dead plants and animals without need for internal digestion
denitrification: the reduction of oxidized forms of nitrogen (nitrates), ultimately resulting in molecular nitrogen
deoxyribonucleic acid (DNA): the carrier of genetic information present in nearly all organisms; forms a double helix
dicot: a flowering plant whose seed has two cotyledons differentiation: the process through which a cell develops and specializes to perform a certain function
GLOSSARY OF TERMS
diffusiondouble helix
diffusion: the movement of particles from an area of higher concentration to an area of lower concentration; does not require energy. The particles will continue to move until they are evenly dispersed.
dihybrid cross: a genetic cross between two parents that are each heterozygous for alternative alleles of two dominantrecessive traits.
domain Archaea: one of the three taxonomic domains of organisms; consists of a specialized group of unicellular prokaryotes that can live in extreme environments
diploid: containing two copies of each chromosome, one from each parent
disaccharide: a double sugar
DNA replication: the synthesis of a new DNA molecule that has the same nucleotide sequences as a preexisting DNA molecule
DNA sequences: the precise ordering of nucleotides within a DNA molecule
domain Bacteria: one of the three taxonomic domains of organisms; includes prokaryotic, single-celled organisms that lack a membrane-enclosed nucleus and can be classified by shape
domain Eukarya: one of the three taxonomic domains of organisms; has cells that contain a membrane-enclosed nucleus
dominant: the property of an allele that causes the allele to be expressed always, even if there is only one copy present
double helix: the primary physical shape of double-stranded DNA molecules
GLOSSARY OF TERMS
ecological pyramidenzyme-substrate complex
ecological pyramid: a representation of the organisms in an ecosystem organized into separate trophic levels with producers at the bottom and top predators at the top
electron transport chain: the transfer of electrons through a series of electron donors and acceptors, which is coupled to the transfer of protons across a membrane, creating a proton concentration gradient that is used to produce ATP
embryo: a multicellular diploid eukaryote in its earliest stage of development, from the time of fertilization until birth, hatching, or germination
endoplasmic reticulum: a system of membrane-enclosed sacs and tubes in the cytoplasm of eukaryotic cells where proteins and lipids are synthesized
endosymbiotic theory: the theory that several key organelles found in eukaryotes originated as a symbiosis between separate single-celled organisms
endothermic: requiring or involving a net input of heat
energy pyramid: a representation of an ecological community showing the total amount of energy contained within each trophic level
environmental factors: external factors that influence living organisms
enzymes: proteins that can change the rates of specific reactions
enzyme-substrate complex: the intermediate formed when a substrate interacts with the enzyme’s active site
GLOSSARY OF TERMS
epididymis: a single, narrow, tightly coiled tube connecting the testicle to its vas deferens
fatty acids: energy-containing biomolecules composed of a carboxylic acid attached to a long hydrocarbon chain
eukaryotic cell: a cell with a defined nucleus and membrane-bound organelles
evaporation: the process by which matter on the surface of a liquid changes from a liquid to a vapor
evolution: descent with modification from a preexisting species
exocytosis: the transport of material out of a cell by means of a transport vesicle that surrounds the material and then merges with the cell membrane, expelling the material inside
feedback mechanism: a system of receptors, control centers, and effectors that maintain homeostasis by sensing, evaluating, and adjusting the body’s internal conditions
exothermic: requiring or involving a net output of heat
fermentation: a metabolic process that converts sugars to acids, gases, alcohol, or a combination of these to produce ATP; does not involve an electron transport chain and produces less ATP than respiration
fertilization: the combination of the sperm and ova to produce a zygote
filament: the slender, stalk-like portion of the male reproductive structure of a flowering plant; supports the anther
GLOSSARY OF TERMS
food chain: a single linear path of energy transfer through the trophic levels of an ecosystem food web: a complex of interconnected food chains showing the trophic interactions in an ecosystem
forensics: gathering and examining information about the past using the scientific method
fossil fuel: a natural, nonrenewable fuel such as coal, oil, or natural gas formed a very long time ago from the remains of living organisms
fossil record: the fossils and their locations in the sedimentary layers of Earth’s crust, which provide information about things that lived in the distant past
fossils: preserved parts or traces of animals and plants that lived in the past
function: the purpose which something serves gametes: cells that contain half the total number of chromosomes for an organism; sex cells
gametophyte: the haploid stage of a plant that produces gametes by mitosis
gel electrophoresis: a technique used in DNA fingerprinting and other processes in which molecules migrate through a gel (such as a polyacrylamide gel) and separate into bands according to size
gene expression: the process by which genetic information generates a specific protein or trait
gene pool: all the genes in any population
GLOSSARY OF TERMS
gene therapyGolgi body
gene therapy: the application of genetic engineering to the transplantation of genes into human cells in order to cure a disease caused by a genetic defect
genes: segments of DNA that code for protein or functional RNA
genetic disorder: a disorder that is caused by an error in the DNA sequence or by the presence or absence of specific alleles
genetic engineering: the deliberate modification of the DNA sequence of an organism by using genetic techniques
genetically modified organism (GMO): an organism whose genetic material has been altered using genetic engineering techniques
genome: the complete set of genes or genetic material in a cell or organism
genotype: the genetic makeup of an organism
germination: the process of sprouting and growing global warming: an increase in the average temperature of Earth’s atmosphere, especially a sustained increase great enough to cause changes in the global climate
glucose: a monosaccharide sugar, C6H12O6, that is produced in photosynthesis and used during cellular respiration for energy
production
glycolysis: the breakdown of glucose into pyruvate to produce ATP and NADH; the first step in both cellular respiration and fermentation
Golgi body: an organelle that packages and sorts materials for transport outside of the cell
GLOSSARY OF TERMS
homeostasis: the tendency for a system, such as a cell, to maintain relatively constant internal conditions gradualismhomeostasis
gradualism: the theory that species evolve slowly and gradually over extended periods of time
gravitropism: a plant’s ability to orient its growth toward (roots) or away from (stems) the center of Earth
heart: an organ made of muscle that pumps blood throughout the body; consists of four chambers: right atrium, left atrium, right ventricle, and left ventricle
herbivores: organisms that consume only plants
greenhouse gas: gases in the atmosphere that trap heat within the atmosphere
guanine: a purine base that pairs with cytosine
guard cells: cells surrounding the stoma that regulate the opening and closing of the stoma
heterotroph: an organism that must consume other organisms for energy
heterozygous: a condition where an individual possesses two different alleles of a gene
histone: a protein that DNA coils around to form chromatin
gymnosperm: a class of plants that produce naked seeds found in cones instead of ovaries
haploid: containing only one copy of each chromosome, from only one parent
GLOSSARY OF TERMS
homologous structuresinterphase
homologous structures: an organ or bone that appears in different animals, underlying anatomical commonalities demonstrating descent from a common ancestor
homozygous: when an individual has two of the same allele for a trait, whether it be dominant or recessive
immune system: biological structures and processes within an organism that protect against disease; includes the skin, nose and nose hairs, tonsils, lymph nodes, lymphatic vessels, lymphocytes (white blood cells), spleen, and thymus
host: an organism within or upon which another organism or virus (parasite, commensal, or mutualist) resides
hydrocarbons: molecules that are composed of carbon and hydrogen atoms
hypertonic: having a higher concentration of solute outside the cell than inside the cell; water will move out of the cell, causing it to shrink.
independent assortment: when inherited traits separate independently when forming gametes, allowing each the same probability of being passed on to offspring
infectious disease: Illness caused by bacteria, viruses, parasites, or fungi that can be passed directly or indirectly to another person
interbreed: to introduce genetic material from one population of a species to anothers
hypotonic: having a higher concentration of solute inside the cell than outside the cell; water will move into the cell, causing it to swell.
interphase: the longest phase of the cell cycle, in which the cell will grow larger and replicate its DNA in order to prepare for cell division
GLOSSARY OF TERMS
interspecifickingdom
interspecific: occurring between two or more species
intraspecific: occurring within a species
invasive species: an alien (non-native to the ecosystem) species, usually brought to an area by humans, that competes for resources and causes problems for the native species within an ecosystem
isolation: a process by which two species that could produce hybrid offspring are prevented from doing so
isotonic: equal concentrations of solute both inside and outside the cell; there is no net movement of water into or out of the cell.
keystone species: a species that, if removed from an ecosystem, would cause a major change in that ecosystem
kingdom Animalia: kingdom of heterotrophic eukaryotes that includes all animals
kingdom Archaea: kingdom of prokaryotic, single-celled organisms that live in extreme environments
kingdom Bacteria: kingdom of prokaryotic, single-celled organisms that lack a membrane-enclosed nucleus and can be classified by shape
kingdom Fungi: kingdom of heterotrophic eukaryotes that reproduce through asexual spores and have cell walls
kingdom Plantae: kingdom of autotrophic eukaryotes that includes all plants
kingdom Protista: kingdom of single-celled and simple multiple-celled eukaryotic organisms
GLOSSARY OF TERMS
Krebs cycleMendel’s law of dominance
Krebs cycle: a part of aerobic respiration that uses the products of glycolysis and fatty acid oxidation to generate ATP and NADH for oxidative phosphorylation
lactic acid fermentation: a biological process that produces lactic acid by the conversion of sugars into cellular energy in the absence of oxygen, generally found in animals and some bacteria
lipid: a member of a diverse group of biomolecules that are hydrophobic and include fats, oils, waxes, and other molecules
lysogenic cycle: a reproductive cycle used by viruses where the virus is incorporated into a host bacterial cell’s genetic material for a period of time
light-dependent reactions: the set of reactions in photosynthesis in which chlorophyll absorbs light energy to make ATP and NADPH
light-independent reactions: also known as the Calvin cycle; the set of reactions in photosynthesis in which the products of the light-dependent reactions are used to make glucose from carbon dioxide and water
limiting factor: a biotic or abiotic environmental factor that restricts the growth of a population
lytic cycle: a reproductive cycle used by viruses where the virus rapidly reproduces in the host cell and then breaks open the host to release the viral progeny
matter: anything that has volume and mass
meiosis: cell division that results in the production of haploid gametes: sperm and eggs
Mendel’s law of dominance: a law stating that when an organism contains two alleles for a trait, the dominant one will be expressed, masking the recessive trait
GLOSSARY OF TERMS
Mendel’s law of independent assortmentmonomer
Mendel’s law of independent assortment: a law stating that each allele pair segregates randomly to the haploid gametes in meiosis, so which allele a gamete receives for one gene is not affected by which allele the gamete receives for another gene
Mendel’s law of segregation: a law stating that allele pairs separate during gamete formation, so each gamete carries only one allele for each gene
messenger RNA (mRNA): a single-stranded nucleic acid, made of RNA, that is a copy of a specific DNA sequence; created by the cell for transferring the genetic information in DNA to a ribosome to make a protein
metabolism: the set of chemical reactions within a cell or organism that maintain life
metaphase: the phase of mitosis where chromosomes line up along an imaginary line (the metaphase plate) in the middle of the cell
mitochondrion: an organelle in the cytoplasm of eukaryotic cells that functions in energy production; the power factory of the cell
mitosis: the phase of the eukaryotic cell cycle in which a single cell divides into two cells
molecule: a group of two or more atoms bonded together by chemical forces, representing the smallest possible unit of a chemical compound that can participate in a reaction
monocot: a flowering plant whose seed has one cotyledon
monohybrid cross: a mating between individuals that have different alleles of a single gene
monomer: a single molecule that can be combined with other molecules of the same type to form a more complex molecule
GLOSSARY OF TERMS
monosaccharidenitrogenous base
monosaccharide: the simplest form of sugar
multicellular: composed of more than one cell
mutation: a change in the DNA sequence of a chromosome
nitrification: the biological transformation of ammonia or ammonium to nitrites and nitrates
mutualism: a relationship between organisms or species that is helpful to both
natural disaster: a force of nature that results in catastrophic consequences
natural selection: differential survival and reproductive success among a group of organisms due to differences in the inherited traits or characteristics of the organisms
nervous system: a group of organs and tissues specialized for the rapid transmission and processing of information
niche: the ecological role played by an organism
nitrogen cycle: the process by which nitrogen is converted between various chemical forms as it cycles among the soil, biosphere, lithosphere, and atmosphere
nitrogen fixation: bacterial action that results in the combination of atmospheric nitrogen with other elements, making nitrogen available for use by plants
nitrogenous base: a nitrogen-containing compound that forms part of a nucleotide; functions as the fundamental unit of the genetic code
GLOSSARY OF TERMS
nonspecific immune responseovary
nonspecific immune response: defense against infection that is not specific to a single pathogen and does not provide long-term immunity
nucleic acid: a nucleotide polymer capable of storing and transferring genetic information
nucleotide: a molecule made of a sugar, a phosphate, and a nitrogenous base; the monomer of nucleic acid
offspring: the product of the reproduction of a new organism produced by one or more parents
omnivore: an organism that consumes both animals and plants
organic: containing the element carbon
organism: a single, self-contained entity that performs all of the basic functions of life
nucleus: the organelle where a eukaryotic organism’s genetic material is located; the control center of the cell
ocean acidification: the process that decreases the pH of the ocean due to an increase in the absorption of carbon dioxide
osmosis: the movement of a solvent across a semipermeable membrane from an area of low solute concentration to an area of high solute concentration to equalize the solute concentrations on both sides of the membrane
ovary : an organ that produces female gametes (ova)
GLOSSARY OF TERMS
oviduct (fallopian tube)phototropism
oviduct (fallopian tube): One of the two fallopian tubes that transport the egg from the ovary to the uterus (the womb)
Pangaea: a hypothetical supercontinent in which all the land continents were connected.
phenotype: the physical expression of a gene or set of genes; the appearance of an organism
phloem: plant tissue that transports sugars produced by the leaves throughout the plant
parasite: an organism that lives in or on another organism (host) and causes harm to the host
parasitism: the symbiotic relationship in which one organism benefits while the other is harmed
phospholipid: a molecule that is made up of a hydrophilic phosphate head and a hydrophobic lipid tail; makes up the cell membrane
passive transport: movement across a cell membrane without using energy
pathogen: a virus, bacterium, or other organism that causes an infectious disease
peptide bond: the type of covalent bond that forms between amino acids
photosynthesis: the process by which autotrophic organisms capture light energy to convert carbon dioxide and water into glucose and oxygen, thereby storing some of the captured energy in chemical bonds
phototropism: the ability of plants and some fungi to grow toward or away from a light source
GLOSSARY OF TERMS
phylogenetic treeprey
phylogenetic tree: a diagram that displays the inferred evolutionary relationships among biological species based on the similarities and differences in their physical and genetic characteristics
pioneer species: the first plant species to grow during primary succession
pistil: the female reproductive structure of a flowering plant; consists of the stigma, style, and ovary
plants: multicellular eukaryotes of the kingdom Plantae
point mutation: a change in a single base pair of a DNA sequence
polar: describes a molecule in which one or more atoms is slightly negative and one or more is slightly positive
pollination: the transfer of pollen from the anther to the stigma in flowering plants
pollinator: something that carries pollen from one flower to the next polygenic: when one trait is controlled by more than one gene
polymer: a large molecule formed by the bonding of smaller molecular units
polysaccharide: a carbohydrate
precipitation: rain, snow, sleet, or hail that falls from clouds in the sky
predation: an interaction between organisms in which one organism captures and consumes another organism
predator: an organism that captures and consumes another organism for nourishment
prey: an organism that is captured and consumed by another organism for nourishment
GLOSSARY OF TERMS
primary successionpyramid of biomass
primary succession: the development of an ecological community in a previously uninhabited location
producer: an organism that is capable of performing photosynthesis, transforming energy from the Sun, and using carbon dioxide and water to make food
protein: a biomolecule made of one or more amino acid polymers joined together by peptide bonds and then folded into a complex structure that performs a specific function
product: the ending substance(s), written on the right side of the chemical reaction arrow, that are created during a chemical change
prokaryotic cell: a cell lacking a nucleus or any other membrane-enclosed organelle
prophase: the first phase of mitosis, in which chromosomes condense, becoming visible, the nuclear membrane dissolves, the centrosomes move to opposite ends of the nucleus, and spindle fibers form
prostate gland: a male reproductive organ that secretes fluid to nourish sperm
protein pumps: proteins that work against a concentration gradient to transport materials in and out of a cell, from areas of low concentration to areas of higher concentration
punctuated equilibrium: a mode of evolution characterized by relatively short bursts of rapid evolutionary change interspersed with long periods of little change
Punnett square: tool used to analyze the possible allele combinations of the offspring between two individuals
pyramid of biomass: a diagram to show the amount of mass present at each trophic level
GLOSSARY OF TERMS
reactant: the starting substance(s), written on the left side of the chemical reaction
arrow, which will be destroyed during a chemical change
recessive: the property of an allele that causes the allele to be expressed only if no different allele is present
recombination: the process by which new combinations of alleles that are not found in the parents are produced in offspring
recycle: to properly dispose of used resources so they can be reprocessed into new products reduce: to make smart purchasing decisions that result in less waste and packaging
replication: the process by which DNA makes a copy of itself
reuse: to find ways to use containers and products multiple times
ribonucleic acid (RNA): a single-stranded nucleic acid that contains uracil instead of thymine; can make tRNA, mRNA, or rRNA
ribosomal RNA (rRNA): an RNA molecule that makes up one component of a ribosome
ribosome: a structure made of protein and rRNA that converts messenger RNA sequences into amino acid sequences with the help of transfer RNAs
rock strata: beds or layers of sedimentary rock having approximately the same composition throughout
salinity: how much salt is in something
GLOSSARY OF TERMS
scrotum: a small muscular sac that contains and protects the testicles, blood vessels, and part of the spermatic cord
season: a change in the Sun’s overhead position due to Earth’s axial tilt
secondary succession: the development of an ecological community in an area that was once inhabited but experienced devastation
seed: the result of a fertilized plant ovule; can be cultivated to produce a new plant
semen: a whitish fluid produced by the male reproductive organs, usually consisting of spermatozoa suspended in other organic materials
seminal vesicle: one of a pair of small, tubular glands that are near the prostate; the primary function of the seminal vesicles involves the production of fluid that makes up a significant percentage of semen.
semipermeable (selectively permeable):
Allowing only some materials to pass through a membrane
sexual reproduction: the reproductive process involving two parents whose genetic material is combined to produce a new organism different from them
sister chromatids: two identical copies of chromatids produced by one chromosome
solvent: a substance in which another substance (solute) is dissolved to form a homogeneous mixture
specialized cells: cells that are specialized to perform a specific function
speciation: the divergence of populations or subpopulations of the same species to the point where they can no longer interbreed and generate fertile offspring
GLOSSARY OF TERMS
specific immune responsestyle
specific immune response: defenses against infection that are specific to a single pathogen and provide long-term immunity
sperm and egg cells: cells that contain half of the total number of chromosomes for an organism; sex cells, called gametes
sperm: haploid male gametes that can combine with a haploid female gamete to form a new organism
spore: a haploid, unicellular structure formed for the purpose of reproduction that can be dispersed and form gametes for sexual reproduction when conditions are favorable
sporophyte: the diploid stage of a plant that produces spores by meiosis
stamen: the male reproductive structure of a flowering plant; consists of the anther and the filament
stasis: a long period of time in which little or no change occurs within a species
stem cell: an undifferentiated cell that gives rise to specialized cells
stigma: the sticky tip of the female reproductive structure of a flowering plant; captures pollen for the purpose of pollination
stoma: a tiny pore in the epidermis of a leaf used for gas exchange
structure: the physical arrangement of the tissues, organs, or organelles of an organism
style: the slender, stalklike portion of the female reproductive structure of a flowering plant; supports the stigma
GLOSSARY OF TERMS
succession: a change in the types of species present in a community over time
surface tension: the elastic tendency of a liquid that makes it acquire the least surface area possible
survival of the fittest: the continued existence of organisms that are better adapted to their environment, with the extinction of others that are not
sustainability: how long something can last
sustainable: capable of maintaining the current community at a steady level without exhausting natural resources or causing severe ecological damage
symbiosis: close interactions that occur between different organisms that live within the same ecosystem
taproot: a primary root that grows down with small lateral roots
taxonomy: the branch of science that formally names and classifies organisms by their structure, function, and relationships
telophase: the phase of mitosis in which the genetic material has been separated and the nuclear membrane begins to re-form to create two separate but identical nuclei
testicles: male reproductive organs that produce sperm cells and hormones
tetrad: a group of four chromatids
theory: a well-supported explanation
thigmotropism: growth of a plant in response to physical contact
thymine: a pyrimidine base that pairs with adenine and is found only in DNA
transcription: the process in which a strand of DNA is copied into an RNA strand for the purpose of protein synthesis
GLOSSARY OF TERMS
transfer
transfer RNA (tRNA): an RNA molecule that is responsible for transporting amino acids to the ribosome to be used in the synthesis of proteins
transgenic organism: an organism whose genetic characteristics have been altered by the insertion of a modified gene or a gene from another organism using the techniques of genetic engineering
translation: the process by which the sequence of nucleotides in a messenger
RNA is converted by a ribosome and transfer RNAs into a polypeptide with a specific sequence of amino acids
transpiration: the movement of water from the roots of a plant through the stem and leaves and into the atmosphere via evaporation
trophic level: an organism’s position on a food chain
unicellular: composed of a single cell
uterus: the female reproductive organ in mammals in which the fertilized egg develops into a fetus and undergoes gestation
vacuole: a large organelle in plant, fungal, and some animal, protist, and bacterial cells that stores water and materials inside the cell
vagina: a sex organ that mainly functions for the facilitation of sexual intercourse and childbirth
variation: the occurrence of an organism, behavior, trait, or gene in more than one form
vas deferens: the tube that connects the testes with the urethra
virus: a particle consisting of genetic material inside a protein capsule that infects host cells and uses components of the host cell to produce more of its kind
RNA (tRNA)virus
GLOSSARY OF TERMS
water cycle: the change of water from one state to another as it moves between Earth’s surface and the atmosphere
weather disturbances: disturbances caused by different weather phenomena
xylem: plant tissue that transports water absorbed in roots throughout the plant
zygote: A diploid cell resulting from the fusion of the sperm and egg
