Name _______KEY__________________
Biology
Final Exam Review Packet
STUDY TIPS
 Use your textbook and your notes to prepare yourself for the Final Exam.
 DON’T CRAM! It’s a proven fact: studying for a little bit each day works better
than waiting until the night before the exam.
 Remember to ask questions in class about concepts you want clarified.
GUIDING QUESTIONS FOR FINAL EXAM
1. Scientific Method
a. What is the difference between an independent and a dependent variable?
IV = what you manipulate in the experiment (what you test the effect of, or
what you change)
DV = what you measure in the experiment (what is affected by the
independent variable)
b. What is a controlled experiment?
A controlled experiment compares the results of an experimental sample to a
control sample, which is practically identical to the experimental sample with
the exception of the ONE aspect that is being tested (aka the independent
variable.)
2. Characteristics of Life
a. What are the 7 characteristics common to all living things?
(Hint: GO RACER)
DNA, cells, growth and development, organization, homeostasis, adaptation
through evolution, reproduction, energy, response to stimuli, and death (all
living things must eventually cease living).
b. Why are viruses not considered to be living things? Use your answer to the
question above.
Viruses do not contain cells, cannot reproduce on their own, and do not
always contain DNA.
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3. Chemical Basis of Life
a. What is the difference between adhesion and cohesion?
Adhesion – Water molecules sticking to other polar surfaces
Cohesion – Water molecules sticking to other water molecules.
b. Why is water important to living things?
Water is important to living things because it is a temperature stabilizer and
serves as an important solvent for the chemical reactions required for life. It
is also a key reactant in photosynthesis, the reaction that enables autotrophs
to fix solar energy into organic food compounds.
c. Why is carbon the main ingredient of organic molecules?
Carbon is a versatile atom that can form four bonds with itself and with other
molecules. It can exist in a variety of stable configurations including long
chains (such as fatty acids) or rings (such as glucose).
d. Describe the building blocks and functions of the four major classes of
biomolecules.
i. Carbohydrates – Building blocks are monosaccharides (simple
sugars). Functions: short-term/medium-term energy storage and cellcell recognition.
ii. Lipids – Building blocks are glycerol and fatty acids. Functions: longterm energy storage, insulation, membrane structure (phospholipids),
membrane fluidity (cholesterol), hormone signaling (testosterone,
estrogen).
iii. Proteins – Building blocks are amino acids. Functions: enzymes,
structure, defense (antibodies), hormones (insulin), receptors/channels
in membranes, etc.
iv. Nucleic acids – Building blocks: nucleotides (each contains a sugar, a
nitrogenous base, and a phosphate group). Functions: genetic
information (DNA/RNA), energy currency (ATP).
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e. Describe the structure and function of an enzyme.
An enzyme is a protein that speeds up chemical reactions by lowering the
activation energy needed for the reaction to occur. It has a binding pocket
known as an active site, which is where the substrate (molecule to be acted on
by the enzyme) binds. Enzymes are not used up or changed in the process.
f. Explain how a change in temperature or pH may affect the function of an
enzyme.
Heating up an enzyme or changing the pH affects the bonds that maintain the
protein’s shape. If the shape of the active site is affected, the substrate may no
longer be able to bind – this is called denaturing of the enzyme. An enzyme
with an altered active site will not be able to function.
4. History of Life
a. Explain what conditions were like on the early Earth.
Earth was created approximately 4.6 billion years ago. The early atmosphere
contained many gases such as ammonia, hydrogen sulfide, and carbon dioxide
– most importantly, there was little to no atmospheric oxygen. There was
intense volcanic activity and the surface was frequently bombarded with
asteroids for much of the planet’s early existence.
b. How and when did life first evolve on Earth? What were the first living
things?
Scientists believe that life first evolved on the planet as early as 3.8 billion
years ago. The first living things were prokaryotes (bacteria) and they
probably first lived underground or at the bottom of the ocean near
hydrothermal vents. These first bacteria were heterotrophs; bacteria that
could perform photosynthesis would not evolve until much later on. These
cyanobacteria would ultimately be responsible for creating enough oxygen in
the atmosphere to allow for the evolution of aerobic cellular respiration.
5. Evolution
a. Who was Charles Darwin? Describe his voyage on the HMS Beagle.
Darwin was an English naturalist who traveled aboard the HMS Beagle from
1831-1836.On his journey, he read the works of Charles Lyell, who believed
that the Earth was much older than previously thought and that gradual
forces continue to shape the planet. He collected thousands of specimens on
his voyage and made observations (such as differences between species on
islands vs. mainland) that ultimately resulted in his theory of natural
selection.
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b. Explain the key features of Darwin’s theory of natural selection and use this
theory to explain the evolution of a given trait (e.g., the neck of a giraffe).
Natural variation occurs among the individuals of any population of
organisms. Some differences may improve the chances of survival of a
particular individual. If the traits that give these individuals a reproductive
advantage are also heritable, that is, passed from parent to child, then there
will be a slightly higher proportion that receive the favorable trait in the next
generation. This is known as differential reproduction. Even if the
reproductive advantage is very slight, over many generations any heritable
advantage will become dominant in the population.
Giraffe example
The ancestor of the modern-day giraffe had a much shorter neck. However, in
populations of these ancient giraffes, there was variation with respect to neck
size – some had shorter necks and others had longer necks. In times when
food was scarce, giraffes with naturally longer necks were better able to find
food and therefore more likely to reproduce and pass on their genes. This led
to a higher proportion of giraffes in the next generation with the trait for
longer necks. This process continually repeated itself, driving the change in
the length of the giraffe’s neck over many generations.
c. What is an adaptation? Give an example.
An adaptation is a trait that increases an organism’s chances of surviving and
reproducing in its environment. A well-adapted organism is said to be “fit”
for its environment. An example of an adaptation would be any instance of
camouflage or the thick fur of polar bears (which enables it to survive in polar
environments).
d. Describe the five major categories of evidence for evolution and give an
example of each.
i. Comparative anatomy – Comparing anatomical structures from living
things. For example, similar bones in humans and chimpanzees hint at
a shared common ancestor.
ii. Fossil record – Examining remains of living things. Fossils reveal that
over time, the toes of horses became progressively smaller and
ultimately fused to form hooves.
iii. Embryology – Examining developmental patterns of organisms. Fish,
chickens, and rabbits all have pharyngeal gill slits, hinting that they
share a common ancestor with gill slits.
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iv. Biochemistry – Comparing DNA and amino acid sequences. All living
things contain the protein cytochrome C – organisms that are closely
related have more similar cytochrome C amino acid sequences.
v. Biogeography – Studying the geographical distribution of biological
species. For example, all flightless birds are naturally found in the
Southern hemisphere only, hinting that the ancestor of these birds
likely evolved after the Southern supercontinent broke off from
Pangea.
e. What are homologous and analogous structures? How do they provide
evidence of divergent and convergent evolution?
Homologous structures – Anatomical parts that have similar structure but
different functions. For example, the bones that make up the bat’s wing
are the same bones that are found in the human forearm, the whale’s
flipper, and the horse’s forelimb, even though all are used quite
differently. This provides evidence of divergent evolution – all of these
species share a recent common ancestor that had these bones..
Analogous structures – Anatomical parts that have different underlying
structure but similar function. For instance, consider the wing of a
butterfly and the wing of a bird. Both function in flight, but one is made of
membranes and the other made of bones. These analogous structures
provide evidence of convergent evolution – the butterfly and bird do not
share a recent common ancestor but have evolved similar
adaptations/traits due to similar environmental pressures.
f. What is a vestigial structure? How does it provide evidence of evolution?
A vestigial structure is an embryological remnant -- an anatomical
structure whose function has been lost in the course of evolution.
Examples include the pelvic/hip bones of snakes and whales, as well as the
human tailbone. These structures provide evidence of evolution because
they point to structures that had a function in a recent ancestor of the
present-day species.
6. Classification and Taxonomy
a. Summarize the levels of hierarchy used in biological classification.
(In order from largest to smallest): Domain, kingdom, phylum, class, order,
family, genus, species
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b. What are the three domains? What are their major characteristics?
1. Domain Bacteria – prokaryotes, unicellular, contains all common bacteria
2. Domain Archaebacteria – prokaryotes, unicellular, contains bacteria that
live in extreme environments.
3. Domain Eukarya – eukaryotes, all cells have a nucleus and organelles,
only domain with unicellular and multicellular organisms.
c. What are the six kingdoms? What are their major characteristics?
1. Kingdom Bacteria – Prokaryotes, contain all common bacteria
2. Kingdom Archaebacteria – Prokaryotes, contain bacteria that live in
extreme environments
3. Kingdom Protista – Unicellular, colonial, and multicellular eukaryotes.
Some are heterotrophic, others are autotrophic.
4. Kingdom Fungi – Unicellular or multicellular heterotrophic eukaryotes.
Include decomposers. Contain a cell wall made of chitin.
5. Kingdom Plantae – Multicellular autotrophic eukaryotes. Contain a cell
wall made of cellulose.
6. Kingdom Animalia – Multicellular heterotrophic eukaryotes. Do not have
a cell wall. Most are capable of movement.
7. Cell Structure/Function and Cell Transport
a. What are the three components of cell theory?
1. All living things contain cells.
2. The cell is the basic unit of structure and function in all living things.
3. All cells come from preexisting cells.
b. Draw and label the parts of a bacterial cell.
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c. Draw and label the parts of a plant cell.
d. Draw and label the parts of an animal cell.
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e. Explain the difference between prokaryotic and eukaryotic cells.
Prokaryotic cells – No nucleus, no organelles.
Eukaryotic cells – Have a membrane-bound nucleus. Have organelles.
f. Describe the function of the following organelles:
i. Nucleus – Contains the DNA, controls cell’s activities.
ii. Nucleolus – Inside the nucleus, makes the ribosomes.
iii. Ribosome – Site of protein synthesis.
iv. Rough ER – Packages proteins made by ribosomes for transport.
v. Smooth ER – Makes lipids, breaks down toxins, releases calcium
vi. Golgi apparatus – Modifies and packages substances for transport into
and out of cell (Post Office).
vii. Vacuole – Sac for storing food or water.
viii. Lysosome – Contains digestive enzymes for breaking down food
molecules.
ix. Chloroplast – Contains chlorophyll, site of photosynthesis
x. Mitochondria – Site of aerobic cellular respiration / ATP production.
xi. Cytoskeleton – Network of microfilaments that supports cell shape and
allows for movement of organelles.
xii. Flagella – “Tails”, function in locomotion.
xiii. Cilia – “Hairs”, function in locomotion
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g. Describe the structure of the plasma membrane. Identify the function of
phospholipids, proteins, cholesterol, and carbohydrates in the membrane.
The plasma membrane consists of a phospholipid bilayer with embedded
proteins that function as enzymes and channels. Cholesterol molecules
regulated the fluidity of the membrane, and carbohydrates function as ID
tags.
h. Describe each of the following mode of cellular transport:
i. Passive transport – Does not require energy. Molecules move from
high concentration to low concentration. Includes simple diffusion,
facilitated diffusion, and osmosis.
ii. Active transport – Requires an input of cellular energy (ATP).
Molecules are either large, have charges, or move from low
concentration to high concentration
iii. Diffusion – Random movement of molecules from areas of high
concentration to low concentration.
iv. Facilitated Diffusion – Just like diffusion, only molecules use a
carrier/transport protein to cross the plasma membrane.
v. Osmosis – The diffusion of water across a semipermeable membrane.
vi. Endocytosis – Active transport mechanism by which a large molecule
is engulfed by plasma membrane and enters the cell in a vesicle.
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vii. Exocytosis – Active transport mechanism by which a large molecule
exits the cell when a vesicle from the Golgi apparatus fuses with the
plasma membrane and releases its contents.
i. Explain what happens to animal and plant cells when placed in hypertonic,
hypotonic, and isotonic solutions.
Hypertonic solution – A solution with more solute (and less water) relative to
the cell. An animal cell placed in a hypertonic solution will shrink; a plant
cell will plasmolyze (cell membrane shrinks inwards from cell wall.
Isotonic solution – A solution with equal amounts of solute and water relative
to the cell. Animal cells placed in isotonic solutions do not experience a net
change in size, while plant cells placed in isotonic solutions are flaccid (weak)
Animal cells prefer isotonic solutions..
Hypotonic solution – A solution with less solute (and more water) relative to
the cell. An animal cell placed in a hypotonic solution will burst; a plant cell
will be turgid (stiff) as a result of maximum water pressure against the cell
wall. Plant cells prefer hypotonic solutions.
8. Cellular Reproduction
a. Draw the cell cycle and describe what happens to the cell in each phase.
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b. Explain what happens during the various stages of mitosis.
c. What is the relationship between control of the cell cycle and cancer?
Cancer results from uncontrolled cell divisions – losing control of the cell
cycle can result in abnormal cell growth (tumors).
d. Compare and contrast mitosis and meiosis.
Mitosis – One cellular division, produces two identical daughter cells that
each have two copies of all chromosomes. Used for asexual reproduction,
growth, and repair.
Meiosis – Two cellular divisions, produces four unique daughter cells that
each have just one copy of all chromosomes. Daughter cells are gametes
designed for sexual reproduction.
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e. How does meiosis promote genetic variation?
Meiosis produces genetic variation during Prophase I when homologous
chromosomes form tetrads and swap portions of the genes from maternal and
paternal chromatids to created recombinant chromosomes. This process is
known as crossing over. Meiosis also contributes to genetic variation due to
the independent assortment of homologous chromosome pairs during
Metaphase I – each daughter cell receives unique combinations of maternal
and paternal chromosomes.
f. What is a karyotype?
A karyotype is an image of an individual’s chromosomes arranged in
numbered pairs from 1-23. These images can be used to identify gender (XX
or XY) and to look for chromosomal abnormalities (Are there two of every
chromosome? Are any damaged?)
g. What is nondisjunction? What are some disorders that can result from errors
of meiosis?
Nondisjunction is the failure of the chromosomes to separate equally during
either Anaphase I or Anaphase II or meiosis. This results in some daughter
cells missing a chromosome or receiving an extra chromosome. Disorders
that result from nondisjunction include Down Syndrome (Trisomy 21),
Klinefelter Syndrome (XXY), and Turner Syndrome (XO).
Name ______KEY___________________
Biology
Final Exam Review Packet
STUDY TIPS
Page 12 of 21



Use your textbook and your notes to prepare yourself for the Final Exam.
DON’T CRAM! It’s a proven fact: studying for a little bit each day works better
than waiting until the night before the exam.
Remember to ask questions in class about concepts you want clarified.
GUIDING QUESTIONS FOR FINAL EXAM
9. Genetics (Chapter 10)
a. Describe the work of Gregor Mendel.
Mendel experimented with pea plants and used cross-pollination techniques to
study the inheritance of various factors. He took meticulous notes/
observations and discovered the basic laws of genetics without knowing
anything about DNA or the structure of genes.
b. What is the difference between a dominant and a recessive allele?
A dominant allele is always expressed in the phenotype. A recessive allele is
only expressed if there are no dominant alleles present.
c. What are Mendel’s laws of segregation and independent assortment?
Law of segregation – When an individual produces gametes, the two alleles
for each gene separate so that each gamete only receives one allele.
Law of independent assortment – Allele pairs separate independently during
the formation of gametes. Basically, this means that the inheritance of any one
trait does not affect or influence the inheritance of a second trait (assuming
the traits are on different chromosomes).
d. Draw Punnett squares for the following crosses: Aa x Aa; DdFf x DdFf.
e. Explain the following exceptions to Mendel’s laws and give an example:
i. Incomplete dominance – One allele is not completely dominant over
the other, so the heterozygous condition is an intermediate phenotype.
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Example: Japanese snapdragons
RR = red
R’R’ = white RR’ = pink
ii. Codominance – Two dominant alleles.
Example: cattle color
RR = Red R’R’ = white RR’ = roan (red and white)
iii. Multiple alleles – More than two alleles determine the phenotype of a
single trait.
Example: Human ABO blood groups
IA = allele for A blood (dominant) IB = allele for B blood (dominant)
i = allele for O blood (recessive)
f. What are sex-linked traits? Why do they typically affect males more often
than females?
Sex-linked traits are traits on the X chromosome. They typically affect males
more often than females because males (XY) only have one X chromosome
and will therefore express all of their sex-linked recessive alleles. Females
(XX) have two X chromosomes and can be carriers of a recessive sex-linked
trait without expressing the phenotype.
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g. What is a pedigree?
10. Molecular Biology (Chapter 11)
a. Describe the structure of DNA.
Shape = double helix. Consists of nucleotides arranged in base pairs. Sugars
and phosphates form the backbone. Strands are antiparallel.
b. Describe the contributions of the following scientists to the discovery that
DNA was the genetic material:
i. Griffith – Injected two types of bacteria into mice. Found that a
mixture of heat-killed pathogenic bacteria and living harmless
bacteria transformed into living pathogenic bacteria and killed mice.
ii. Avery – Confirmed that the transforming agent from Griffith’s
experiment was the DNA from the heat-killed bacteria.
iii. Hershey and Chase – Verified that DNA was the genetic material by
radioactively labeling the proteins and DNA of phage and using a
blender to determine which radioactive component penetrated
bacteria cells.
c. Describe the contributions of the following scientists to the discovery of the
structure of DNA:
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i. Chargaff – Determined the base-pairing rules by observing that the
number of A’s always equals the number of T’s in DNA (same for C’s
and G’s).
ii. Franklin – Used X-ray crystallography to determine the double helical
structure of DNA.
iii. Watson & Crick – Built the first accurate model of DNA.
d. How does the structure of DNA suggest a replication mechanism for DNA?
The double helix consists of complementary strands, which suggests that you
could replicate DNA by unzipping the two strands and using each parent
strand as the template for making a new copy of the DNA.
e. Describe the steps of DNA replication.
1. Helicase unwinds the DNA.
2. Primase makes RNA primers.
3. DNA polymerase synthesizes new DNA on the leading strand from 5’ 3’
(working towards the replication fork).
4. On the lagging strand, DNA polymerase works away from the fork,
synthesizing new DNA in short pieces called Okazaki fragments.
5. Ligase joins Okazaki fragments on the lagging strand.
6. DNA polymerase replaces the RNA primers with DNA.
f. What is the difference between the leading and the lagging strand?
Leading strand is synthesizes in continuous fashion, whereas the lagging
strand is synthesized in short pieces and therefore takes longer. This is due to
the antiparallel nature of DNA and the fact that DNA polymerase only works
in the 5’ 3’ direction.
g. What is the central dogma of biology?
DNA  mRNA  protein
h. Compare the structure of DNA with RNA.
DNA: double helix, sugar is deoxyribose, bases A-T, C-G
RNA: single strand, sugar is ribose, bases A-U, C, G
i. Explain what happens during transcription.
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DNA is copied into mRNA by RNA polymerase. This needs to happen because
DNA contains the instructions for making protein, but the instructions need to
get from the nucleus (where DNA is stored) to the ribosome (site of protein
synthesis).
j. Explain what happens during translation.
mRNA attaches to the ribosome, which “reads” the mRNA codons (sets of
three bases) at a time and recruits the appropriate tRNA molecule. Each tRNA
molecule is attached to a specific amino acid, the building blocks of protein.
The protein is assembled as tRNA molecules bind to the mRNA and the amino
acid that the tRNA delivers is added to the growing protein chain. Translation
always begins with a start codon (AUG, which brings the amino acid Met)
and ends at a stop codon (UGA, UAA, UAG).
k. How does the genetic code provide evidence for evolution?
All living things use the same genetic code, which suggest that this code was
used for protein synthesis in a common ancestor of all living things.
l. What is a mutation?
A change to the DNA.
m. Distinguish between the following types of mutations:
i. Silent – Does not affect protein synthesis – the mutation codes for the
same amino acid.
ii. Missense – A different amino acid is used during protein synthesis (a
substitution).
iii. Nonsense – A premature stop codon.
11. Cellular Respiration
a. How does ATP provide energy for cellular work?
ATP has high-energy bonds between its phosphate groups. Breaking the bond
between the 2nd and 3rd phosphate group releases energy that can be coupled
to an endergonic reaction.
b. What is the difference between anaerobic and aerobic respiration?
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Anaerobic – does not require oxygen. Consists of glycolysis and either lactic
acid fermentation (muscles) or alcoholic fermentation. Net gain of 2 ATP
molecules per glucose.
Aerobic – requires oxygen. Consists of glycolysis followed by Krebs cycle and
electron transport chain. Net gain of 36-38 ATP molecules per glucose.
c. What is the overall equation for aerobic cellular respiration?
C6H12O6 + 6O2 --> 6CO2 + 6H2O + energy
d. Describe the structure of the mitochondrion.
e. Explain what happens during glycolysis and where it takes place.
Glucose is broken down into two pyruvate molecules. 2 ATP molecules are
needed to start the process, but 4 are produced, resulting in a net gain of 2
molecules. NADH molecules are generated for use in the electron transport
chain. Occurs in the cytoplasm.
f. Explain what happens during the Krebs cycle and where it takes place.
Occurs in the mitochondrial matrix. Each pyruvate molecule is broken down
into carbon dioxide, generating NADH and FADH2 molecules for use in the
electron transport chain as well as a total of 2 ATP molecules per glucose.
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g. Explain what happens during the electron transport chain and where it takes
place.
NADH and FADH2 molecules drop off their electrons to proteins in inner
membrane of mitochondria. As electrons are passed along chain, hydrogen
ions are pumped into the intermembrane space. Oxygen ultimately accepts the
electrons and combines with hydrogen ions to create water. Hydrogen ions
flow back through the membrane (down their concentration gradient),
powering an enzyme that makes 32-34 ATP molecules per glucose.
h. Why does fermentation take place in cells that lack mitochondria or when
there is not enough oxygen present?
Fermentation is necessary to recycle the electron carrier NAD+ and to
complete the breakdown of pyruvate.
12. Photosynthesis
a. How do autotrophs use light energy to make food?
Sunlight is used to make ATP. ATP is then used to produce sugar molecules
from carbon dioxide and water.
b. What is the overall equation for photosynthesis?
6CO2 + 12H2O + light → C6H12O6 + 6O2 + 6H2O
c. What are the major parts of a leaf and their functions?
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d. Describe the structure of the chloroplast.
e. Explain what happens during the light-dependent reactions.
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Electrons in chlorophyll molecules (stored in the thylakoid) are excited by
sunlight. These high-energy electrons are passed down an electron transport
chain to generate ATP molecules (as in cellular respiration). Water is split to
replace these electrons, releasing oxygen gas. ATP is used in lightindependent reactions to make sugar.
f. Explain what happens during the dark-dependent reactions.
In the stroma, ATP and carbon dioxide are used to make glucose molecules.
This is also called the Calvin cycle.
g. Identify two factors that affect the rate of photosynthesis.
Temperature
Light intensity
Amount of carbon dioxide
h. Explain the complimentary nature of photosynthesis and cellular respiration.
They are opposite processes – the products of one are the reactants of the other.
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