Biology 123 SI Mock Exam 4
1. Which of the following characteristic, structure, of process is shared by viruses,
bacteria and eukaryotes?
a. Genetic material composed of nucleic acids
b. Cell division
c. Membrane bound organelles
d. Metabolism
e. Glycolysis
2. A bacterium infected with a new virus composed of a T2 phage protein coat and
T4 phage DNA would create new phages composed of
a. T2 protein and T4 DNA
b. T4 protein and T2 DNA
c. T4 protein and T4 DNA
d. None of the above
3. A biologist analyzes an enveloped RNA virus that is present in monkeys. Upon
analysis, the viral envelope is discovered to contain a protein that is characteristic of
monkey cells. What is the most likely explanation of this?
a. The virus uses the protein to fool the host cell into recognizing the virus as “self”
b. The cells are made of virus, therefore it will have the same proteins
c. The viral envelope is constructed as the virus is leaving the host cell
d. The virus has evolved to become integrated into all monkeys
e. Not enough information is present.
4. In the lytic cycle of phages...
a. The cell typically dies releasing many new phages
b. DNA replication does not occur
c. The cell takes in all components of the phage
d. The phage’s genome is integrated into the host’s genome
5. Plant viruses spread through plants by way of
a. Plasmodesmata
b. Lymphatic system
c. Central vacuoles
d. chloroplasts
6. Under what conditions would you most likely observe a prophage?
a. When observing the genetic material of a cell infected by a virulent phage
b. When observing the genetic material of a cell infected by a temperate phage
c. When observing the genetic material of a cell infected by a phage with restriction
enzymes
d. When a cell is attacked by either type of phage containing RNA as its genetic
material
7. The phage reproductive cycle that immediately kills the host cell is
a. Lytic cycle
b. Virulent cycle
c. Lysogenic cycle
d. Temperate cycle
8. What are prions and how are they thought to cause disease?
a. Virus capsids that encase host cell's receptor proteins cutting them off from
nutrient supply.
b. Abnormally shaped proteins that induce normal proteins to take on the abnormal
form.
c. Rare mutated pieces of plant genome that can insert themselves into a host plant's
genome at any point.
d. Abnormally shaped plasma proteins in the blood that cause the infection to be
spread throughout the entire body by mutating bone marrow.
9. Retroviruses work via reverse transcription which is
a. The copying of RNA information into DNA
b. The copying of DNA information into RNA
c. RNA being translated into proteins
d. RNA being created from the translation of proteins
10. How did Darwin originally define evolution?
a. Descent with modification
b. Mutation over time
c. Passing of acquired characteristics
d. Naming based on similarities between organisms
11. Vestigial organs are...
a. Small and somewhat useless structures.
b. Remnants of organs used by an evolutionary ancestor
c. Organs that are small but incredibly important
d. Large organs that perform a multitude of functions
e. Both a and b
12. You observe two aquatic organisms living in lakes that contain complex
networks of waterfalls. One of these organisms is known to have evolved from
marsupials, and one from eutherian mammals. Each organism has specialized fins to
help them jump over rocks and move about the waterfall network. How could you
best define these specialized fins?
a. Passing of acquired characteristics
b. Analagous structures
c. Homologous structures
d. Random mutation
13. Which of the following options would allow a host cell to live the longest?
a. A prophage infecting the cell
b. A virulent phage infecting the cell
c. A temperate phage infecting the cell
d. A provirus infecting the cell
14. What is Linnaeus most famous for?
a. Formulating the theory of evolution
b. A geologist that proposed gradualism
c. He was known as the father of paleontology and proposed catastrophism
d. He developed the binomial naming system to classify organisms
e. He proposed that certain factors were set in place to keep the size of populations
in check.
15. You are studying two different organisms that are distantly related. Knowing
only this, which of the following is most likely true?
a. The organisms belong to the same genus but not the same phylum
b. The organisms belong to the same class but not the same order
c. The organisms belong to the same genus but not the same domain
d. The organisms belong to the same family but not the same kingdom
17. Which of these can evolve?
a. A duck forced to live in a stream that is slowly drying up
b. A species of squirrel living in a forest that was recently burned down
c. A school of fish in a stream that a pesticide has recently been introduced to
d. Both b and c
18. Natural selection...
a. Requires that members of the population survive long enough to reproduce
b. Requires that the population not grow too big for all the offspring to survive
c. Requires that there be enough resources for every member of the population to
have their share
d. Creates new traits that are usually beneficial to the population in some way
e. Requires that every member of the population be genetically identical
19. What did not support the theory of evolution?
a. Vestigial structures
b. Taxonomy
c. Comparative biochemistry
d. Fossil records
e. None of the above
20. A fruit fly population has a gene with 2 alleles, A1 and A2. Tests show that 40%
of gametes produced contain the A1 allele. If the population is in Hardy-Weinberg
equilibrium, what proportion carries the A1 and A2 allele?
a. 0.48 b. 0.42 c. 0.09 d. 0.70
21. What is the main source of genetic variation in humans?
a. Natural disasters that separate human populations
b. Genetic drift due to small populations
c. The recombination of alleles during sexual reproduction
d. The bottleneck effect
22. True of False, the human fingerprint is an example of neutral variation.
23. Which is required for Hardy-Weinberg equilibrium to occur?
a. Random mating, no natural selection, and a large population, no gene flow, no
mutations
b. Large population, selective mating, and no natural selection
c. Small population, random mating, and no mutations
d. Small population, high natural selection, and selective mating
24. What does the 2pq in the Hardy-Weinberg equation represent?
a. The percentage of homozygotes
b. The percentage of the population lost to natural selection
c. The percentage of heterozygotes
d. The variation caused by the recombination of alleles during sexual reproduction
I.
Preservation of Genetic Variation (neutral variation)
A. Diploidy
B. Balancing Selection
i.
Heterozygote Advantage
ii.
Frequency-Dependent Selection
Know the 4 reasons why natural selection can’t make a perfect organism.
25. A population is found to be 60% homozygous dominant. What portion of the
population is heterozygous?
a. 77% b. 22% c. 35% d. 4.8%
26. Which type of mutation plays the most important role in increasing the number
of genes in the gene pool?
a. Point mutation
b. Rearrangement of gene loci
c. Duplication
d. No mutation increases the number of genes in the gene pool
27. A number of mosquito populations today are resistant to insecticides that were
once quite effective. Biologists think that insecticide resistance evolved in
mosquitoes because ...
a. Mosquitoes attempted to adapt to the environment
b. Insecticides simply aren’t potent enough
c. Some mosquitoes were already immune to the insecticide and reproduced
d. A new allele occurred out of necessity
29. Sexual recombination results in the shuffling of chromosomes during ____ and
_____.
a. Mitosis, fertilization
b. Meiosis, genetic drift
c. Meiosis, fertilization
d. Mutation, mitosis
30. When gene flow between two populations ceases due to a difference in
geographic area, what has the potential to occur?
a. Allopatric speciation
b. Sympatric speciation – habitat differentiation, polyploidy, and sexual selection
c. Bottleneck effect
d. Sexual selection
31. Two species that have historically been regarded as different species are now
beginning to be listed as the same species by the scientific community. What can you
infer has happened?
a. The two species have evolved to appear to be the same species
b. The two species now live exclusively in the same areas
c. The two species have successfully interbred to produce fertile, viable offspring
d. Scientists are attempting to consolidate the taxonomic system
32. Which species concept defines a species as a set of organisms with a similar
genetic history?
a. Morphological species concept
b. Ecological species concept
c. Phylogenic species concept
d. Biological species concept
33. Which is an example of a post-zygotic reproduction barrier?
a. One species of snake only lives in the trees, while another species only lives in
water
b. One species of bird mates at night while the other mates during the day
c. The egg of one species of goat will reject the sperm from another species
d. The offspring from the mating of two species will not survive to sexual maturity
e. One species of lizard displays a colorful neck flap to attract mates while another
species performs a courtship dance
34. About how old is the earth?
a. 3.5 billion years b. 2.1 billion years c. 4.6 billion years d. 200 million years e. 200
billion years
35. What are thought to be the first self-replicating molecules?
a. RNA
b. DNA
c. Proteins
d. Amino acids
Production of Simple Cells
1. abiotic synthesis of small organic molecules, such as amino acids and
nitrogenous bases
2. The joining of these small molecules into macromolecules, such as proteins
and nucleic acids
3. The packaging of these molecules into protocells, droplets with membranes
that maintained an internal chemistry different from that of their
surrounding
4. The origin of self-replicating molecules that eventually made inheritance
possible
36. What is the main function of Hox genes? Paedomorphosis, heterochrony
a. Provide positional information to animal embryos
b. Provides rate and timing information to animal embryos
c. Create new alleles for adaptation
d. Replicate the genome to cause polyploidy
e. None of the above
37. If a bacteria is shown to be gram negative, what does it look like, and what does
this say about its cell wall?
a. They will be stained by the crystal violet, and have a large peptidoglycan layer
b. They will be stained by the safranin, and they have a relatively small
peptidoglycan layer
c. They will be stained by the safranin, and have a large peptidoglycan layer
d. They will be stained by the crystal violet and have a relatively small peptidoglycan
layer
38. What do bacteria have that eukaryotes do not?
a. Cell walls
b. Photosynthetic pigments
c. A nucleoid region with circular
chromosomes d. Membrane enclosed organelles
e. DNA
39. What does the presence of an F+ plasmid mean for the bacteria?
a. The bacteria is more susceptible to antibiotics
b. The bacteria can produce a sex pillus
c. The bacteria is able to fix nitrogen
d. The bacteria is more resistant to certain antibiotics
40. What is true about conjugation?
a. The bacterial genotype is altered by the uptake of loose DNA in the bacteria’s
environment
b. The process of new virus formation through the use of the bacterial replication
machinery
c. The bacteria acquires new DNA from other bacteria through the use of a pillus
d. The process of a bacteria acquiring new genetic information from viruses that are
unable to replicate
41. Some bacteria can survive even when their main food source is exhausted, and
become active again when the food source is returned. How is this possible?
a. These bacteria produce endospores
b. These bacteria produce exotoxins
c. These bacteria produce endotoxins
d. These bacteria have a cell wall that contains peptidoglycans
42. You observe a bacteria that utilizes organic compounds for both its carbon and
energy source. What classification best fits this bacteria?
a. Photoautotroph
b. Chemoautotroph c. Photoheterotroph d. Chemoheterotroph
TABLE 27.1
Table 25.1