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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 (Chapter 2)
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 (Chapter 1)
a. What are the ten characteristics common to all living things?
(Hint: GO RACER)
G-growth
O-orgnaziation
R-reproduction
A- Adaption through Evolution
C-Cells
E-energy
R-response to stimulus
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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.
3. Chemical Basis of Life (Chapters 4-5)
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).
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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).
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 (Chapter 16)
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 (Chapter 14)
a. Who was Charles Darwin? Describe his voyage on the HMS Beagle.
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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.
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.
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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.
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.
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6. Classification and Taxonomy (Chapter 15)
a. Summarize the levels of hierarchy used in biological classification.
(In order from largest to smallest): Domain, kingdom, phylum, class, order,
family, genus, species
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 (Chapter 6)
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.
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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
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:
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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.
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 (Chapter 9)
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.
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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.
e. How does meiosis promote genetic variation?
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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).
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