Download Exam Review Answers

Conestoga High School
Accelerated Biology
Final Exam
Test Date: Tuesday June 16th at 9:30 AM
Room Number: Period 4 = 125
Period 5 = 128
Period 6 = 131
Format: There are two parts to the exam – a multiple choice section and
a free response section.

Part I: 100 Multiple Choice Questions – distributed as follows:
Unit
Genetics
% of Questions
6%
DNA
29%
Evolution
17%
Ecology
40%
Chapters
7: Extending Mendelian Genetics
8: From DNA to Proteins
# of Questions
6
29
9: Frontiers of Biotechnology
10: Principles of Evolution
11: The Evolution of Populations
13: Principles of Ecology
14: Interactions in Ecosystems
15: The Biosphere
17
40
16: Humans Impact on Ecosystems
Taxonomy/Survey
of Kingdoms
8%
17: The Tree of Life
TOTAL # OF MULTIPLE CHOICE QUESTIONS

8
100
Part II: 50 Free Response Questions (very short - words or 1-2
sentences)
UNIT 1 – GENETICS
Terms to Know:
Dominant – an allele (or trait) that can hide the appearance of another
Recessive – an allele (or trait) that can be hidden by a dominant allele
Genotype – the genetic composition of an organism (ex/Tt)
Phenotype – the physical appearance of an organism – the traits that are actually
expressed (Ex/Tall)
Heterozygous – Having one dominant and one recessive allele in a genotype (Ex/Aa)
Homozygous – Having two of the same alleles in a genotype (Homozygous dominant =
AA; Homozygous recessive = aa)
Sex chromosomes – The X and Y chromosomes in humans; Females = XX, Males = XY
Sex linked traits – traits carried on the X chromosome; sex linked disorders are seen
more often in males
Incomplete dominance – one allele is not completely dominant over another allele for a
particular gene
Co-dominance (and give example) – two alleles are equally expressed (EX/AB blood)
Polygenic Trait (and give example) – more than one pair of alleles codes for a single trait
Ex/Skin color
1. Fill in the following chart on blood types:
Phenotypes
Type A
Type B
Type AB
Type O
Genotypes
AA
AO
BB
BO
AB
OO
2. A woman of blood type A marries a man of blood type B. Is it possible for them to have a child with
type O blood? Yes
A
B
AB
AO X BO
O
AO
O
BO
OO
Explain by showing the cross below:
Genotypic Ratio ¼ AB; ¼ AO; ¼ BO; ¼ OO
Phenotypic Ratio ¼ Type AB; ¼ Type A; ¼ Type B; ¼ Type O
3. Who displays sex-linked disorders more frequently, males or females? males
Why? Because they only have one X chromosome, they only need one copy of the
disease allele to have the disease (Females need to inherit the allele from both
parents)
UNIT 2 – DNA
4. What is the function of DNA? Contains genetic information of the cell and directs all
cell’s activities by directing protein synthesis
5. What are the three parts of a nucleotide? Which part gives the nucleotide its name?
Nucleotide = 1. sugar (deoxyribose in DNA, ribose in RNA)
2. phosphate group
3. base (A,T,C,G)
Nucleotide name = base name
6. Which bases get paired? A
T;
C
G
7. Who discovered the double-helix nature of the DNA molecule? Watson & Crick
8. Complete the chart below that compares DNA to RNA:
Characteristic
# of strands
Sugar
Bases
Types
Where found in cell
DNA
RNA
2
Deoxyribose
Adenine, Thymine
Guanine, Cytosine
N/A
Nucleus
1
Ribose
Adenine, Uracil
Guanine, Cytosine
mRNA, tRNA, rRNA
Nucleus and in cytoplasm
The following questions refer to the following sequence of mRNA:
UUUGCGCCCACU
9. What would the DNA sequence be that this mRNA was made from?
AAACGCGGGTGA
10. Using the table on page 230 of your textbook – what series of amino acids would be encoded by
the mRNA below?
UUU - GCG - CCC - ACU (from above)
phenylalanine – alanine – proline – threonine
11. Each triplet that codes for an amino acid is called a codon
12. What cell organelle moves along the mRNA during translation? Ribosome
13. Complete the following chart that compares the two phases of protein synthesis:
Definition
Where it occurs
DNA involved? (Yes/no)
Transcription
Translation
the process of synthesizing
mRNA by using one strand
of a DNA molecule as a
template
Nucleus
yes
uses the codons in mRNA
molecules to specify the
sequence of amino acids in
polypeptide chains
In cytoplasm on ribosomes
No
Terms to Know:
Genetic engineering – making changes in the DNA code of a living organism
Genome – a complete collection of an organisms genes
DNA Fingerprint – the unique pattern of bands that an individual’s DNA creates after
being cut up and separated in a gel
Restriction Enzymes – enzymes that recognize and cut DNA at specific sites
Plasmids – small, circular pieces of bacterial DNA that replicate when the bacteria
divides; are very useful in genetic engineering
Recombinant DNA – DNA created from splicing together DNA two different species
Cloning – process that creates many identical cells
14. Briefly outline the steps that use recombinant DNA to produce a useful protein like insulin:
1- Plasmid is isolated from bacterial cell and cut with
restriction enzyme
2- Gene of interest is isolated from a cell of the organism, cut
by the same restriction enzyme
3 – Plasmid and gene of interest are combined creating
recombinant DNA
4 – Recombinant plasmid is put into a new bacterial cell
5 – Bacterial cell with recombinant plasmid divides repeatedly
creating clones
6 – Cells are screened to isolate those with the recombinant
plasmid
15. Briefly explain how gene therapy works.
Gene therapy replaces a patient’s defective gene with a good
gene
16. Briefly explain how gel electrophoresis can be used to create a DNA
fingerprint.
DNA sample is “chopped-up” with restriction enzymes creating
multiple fragments of various sizes. This DNA is then loaded into
wells of an agarose gel. An electrical current is applied to the gel
and the fragments (that are negatively charged) start moving
towards the positive end of the gel. Longer fragments have a harder time moving
through the gel, so they don’t move as far as the smaller fragments. The fragments
can then be stained with a dye so that a DNA “fingerprint” can be seen.
UNIT 3 – EVOLUTION
Terms to Know:
Darwin – proposed the theory of Natural Selection after observations he made on the
Galapagos Islands; noticed that many organisms seemed to have adapted to the
environments in which they lived
Fitness – ability of an organism to survive AND reproduce in its specific environment
Adaptation – process by which a population becomes better suited to its environment
Natural selection – a process by which organisms that have traits better suited to their
environment are more successful at surviving and reproducing than those who are not
as well suited to that environment
Homologous structures vs analogous structures – Homologous structures are those with the
same anatomical structure but not the same function (EX: wing of a bat and arm of a
human)
Analogous structures are those with same function but not same structure (EX: wing
of a butterfly and wing of a bat)
Vestigial structures (and give examples) – a structure seen in an organism that has no
apparent function (EX: human tailbone, appendix)
Genetic drift – when allele frequencies of a population change (Equilibrium = when they
remain constant)
Species – members of a population that can mate and produce fertile offspring
Geographic isolation – separation of a population by some physical barrier such as a river
or mountain
17. Why must organisms compete for resources?
Because resources are limited
18. How can similar anatomical features (homologous structures) give evidence of evolution?
Because it can show evidence of a common ancestor
19. What can be learned by comparing DNA sequences (or amino acid sequences of proteins) of
different species?
Species with more similar DNA or amino acid sequences are more closely related
20. Explain the differences between stabilizing, disruptive, and directional selection. Use graphs to
help you answer the question.
a) stabilizing: Favors intermediate phenotypes (extremely light and dark mice
are eliminated)
b) disruptive/diversifying: Favors individuals at both extremes of phenotypic
range (intermediates are eliminated)
c) directional: One phenotypic extreme is favored, while the other is eliminated.
21. What determines whether a new allele (from a mutation) increases its frequency in a
population?
If the new allele increases the fitness of the individuals who express that allele,
then the allele will increase in frequency
UNIT 4 – ECOLOGY
Terms to Know:
Ecology – study of the interaction of living organisms with each other and with their
physical environment
Population – members of the same species living in the same area
Community – group of organisms of different species living together in a particular place
Ecosystem – a community of organisms along with the physical aspects (soil, climate,
water) of their environment
Habitat – where an organism lives
Niche - Where an organism lives, its trophic level, climate & when it reproduces
Producers vs Consumers – P: Organism that can make organic materials for an ecosystem
(EX/plants); C: organism that must eat other organisms (EX/animals)
Herbivores vs Carnivores vs Omnivores – H: plant eaters; C: meat eaters; O: eat both plants
and meat
Food chain vs Food web – Chain: a linear sequence of feeding relationships; Web: a set of
interconnected food chains
Symbiosis – relationship between two organisms in an ecosystem
Limiting factors – something that controls the growth or size of a population
Carrying capacity – maximum number of members of a population of a particular species
that a particular area at a particular time can sustain
Succession – The transformation of an environment over time
Desertification – a process that turns land into an area unable to support plant life;
results from overgrazing, farming, climate change and drought
Species diversity – the number of different species in the biosphere or in a particular area
Ecological footprint - Total area of functioning land and water ecosystems needed to
provide resources and remove wastes that an individual or population generates
22. What are the major processes of the water cycle and
how are they related? (a diagram may help)
Precipitation: water moving from atmosphere
to ground
Evaporation: water moving from ground to
atmosphere
Transpiration: water vapor moving from
plants/animals to atmosphere
23. What are the major processes of the carbon cycle and how are they related? (a diagram may
help)
Photosynthesis: takes Carbon out of
atmosphere
Respiration: puts Carbon back into
atmosphere
Burning of fossil fuels: puts Carbon back into
atmosphere
Decomposition: moves Carbon from organisms
back to the soil
24. How can humans affect the carbon cycle?
Burning fossil fuels
Clearing forests
Destroying vegetation that absorbs CO2
25. What organisms carry out nitrogen fixation?
Bacteria
26. List and describe the three kinds of symbiotic relationships that can occur in an ecosystem
mutualism
parasitism
commensalism
both members benefit
one member benefits and the other is harmed
one member benefits and the other is neither helped nor harmed
27. What factors play a role in population growth rate?
Immigration (+), emigration (-), birth rate (+), death rate (-)
28. Explain the difference between logistic and exponential growth. Include graphs.
Logistic = growth slowed by limiting
factors:
Exponential = growth under ideal
conditions:
29. Explain the difference and give examples of density-dependent vs. density-independent limiting
factors.
Density independent = Regulating factors that affect members of a population
regardless of density
EX/ Weather events (drought, hurricanes, floods) or other natural
disasters (earthquakes & volcanic eruptions)
Density Dependent = Regulating factors that affect members of a population more
if the population is more dense, less if the population is less dense
EX/ Predation, disease, parasites, competition
30. Explain the difference and give examples of renewable vs non-renewable resources.
RENEWABLE
Resources that can be replenished in
a reasonable amount of time
Water, wind, a few trees
NON-RENEWABLE
Resources that can not be replenished in a
reasonable amount of time
Fossil fuels, entire aquifers, entire forests
31. What is the effect of CFC’s in the atmosphere?
Breaks down Ozone
32. What is the greenhouse effect?
A natural phenomenon that maintains the Earth’s temperature range
NOTE: Enhanced greenhouse effect (caused by overproduction of greenhouse
gasses) is bad  leads to global warming
33. What is the goal of sustainable development?
To provide for human needs while preserving our ecosystems
34. Why is biodiversity important? What are some threats to it?
It can contribute to agriculture and medicine.
It is threatened by introduced (invasive) species, habitat fragmentation,
biological magnification of toxic compounds
UNIT 5 – TAXONOMY/SURVEY OF KINGDOMS
35. Explain how binomial nomenclature works.
It is a two-name naming system where the first word represents the genus of the
organism and the second word represents the species. First word is capitalized,
second is not. Both words are underlined or written in italics.
EX/ Felis domesticus = cat
(genus = Felis, species = domesticus)
36. List the levels of biological hierarchy from kingdom to species.
Kingdom  phylum  class  order  family  genus  species
37. Complete the following chart that compares the kingdoms of life
Kingdom
Archaea
Eubacteria
Protista
Fungi
Plantae
Animalia
Pro/Eukaryote? Uni/Multicellular? Autotroph/Heterotroph?
Cell wall contains
Prokaryote
Unicellular
Some A some H
No peptidoglycan
Prokaryote
Unicellular
Some A some H
Peptidoglycan
Some A some H
n/a
H
Chitin
Eukaryote
Eukaryote
Most
Unicellular
Most
Multicellular
Eukaryote
Multicellular
A
Cellulose
Eukaryote
Multicellular
H
n/a