Download Key for Exam 2 Part 1 - Evolutionary Biology

This exam is worth 100 points
Evolutionary Biology
Exam II Part I
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A. Multiple Choice Questions. Choose the best possible answer. Use the bubble sheet.
1. Ducks have webbed feet. The trait of webbed feet in the common ancestor of ducks:
(A) appeared in ancestral ducks because they lived in water and needed webbed feet to swim
(B) appeared in ancestral ducks because of chance mutation(s) (C) appeared in ancestral
ducks because they helped them fly (D) none of the above (E) all of the above.
2. The weakness of the hypothetico-deductive method in explaining how science is really done is
that it (A) neglects the role that experiments have (B) neglects the role that predictions play (C)
neglects the roles that other scientists have (D) neglects the law of parsimony (E) under values
the importance of historical sciences like geology.
3. A group of 100 ducks is taken to a zoo where they are put in a cage that has a lot of food, but
no big pools of water. The cage is only three feet high so the ducks can’t fly very well. The
ducks are allowed to breed. We expect that the offspring of these zoo ducks: (A) will not
have wings (B) will not have webbed feet (C) will have much smaller feet than their parents
(D) will have feet very similar to their parents feet (E) both A and B.
4. Why is it that the Galapagos Islands had an impact on Darwin’s views? (A) Darwin could see
evolution changing the species during his visit (B) He found giant fossil armadillos there
(C) He could see that Lamarck’s views could not be correct (D) He noted that the closely
related species lived on the islands and were similar to those of the mainland (E) While
visiting, he read Charles Lyell’s books on geology stating that the earth slowly changed and
so did the species)
5. The chemical DDT is used to kill mosquitoes in many countries. In the lab, you expose 1000
mosquitoes to DDT and it kills 991 of the mosquitoes. The mosquitoes that survived: (A) by
chance were able to resist DDT (B) evolved to be able to resist DDT (C) were faster than
the other mosquitoes (D) learned to be able to resist DDT (E) both A and D.
6. Which of the following would not be found in a eubacterium but would be found in an
eukaryote? (A) endoplasmic reticulum (B) circular chromosome (C) messenger RNA
(D) plasma membrane (E) cell wall
7. What is the proportion of alleles likely to be shared by a human child and his biological
father? (A) all (B) 3/4 (C) 1/2 (D) 1/4 (E) 1/8
8. Suppose in rats, black fur is dominant over white. If a white rat is crossed with a
heterozygous black rat, what is the likely % of the offspring that will be white?
(A) 0% (B) 25% (C) 50% (D) 75% (E) 100%
9. Suppose this breeding combination occurred: RrYy x rryy. And suppose RY are linked
together & ry are linked together. Which mating combinations would NOT be possible if RY
were linked & ry were linked? (A) rryy (B) RrYy (C) RRyy (D) All are possible (E) none of
the above
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10. Which of the following is NOT required for a population at Hardy-Weinberg equilibrium?
(A) No migration between populations (B) Natural selection is not acting on the alleles in the
population (C) Mating is random (D) Multiple alleles must be present at every locus (E)
All of the above
11. Which of the following traits evolved most recently? (A) prokaryotic cells
(B) eukaryotic cells (C) multicellularity (D) photosynthesis (E) hereditary mechanisms.
12. The fitness of a genotype is a function of the (A) average rates of survival and reproduction
of individuals with that genotype (B) individuals that have the highest rates of both survival
and reproduction (C) individuals that have the highest rates of survival (D) individuals with
the highest rates of reproduction (E) average reproductive rate of individuals with that
genotype.
13. The phenotype of an organism is (A) the type specimen of its species in a museum (B) its
genetic constitution, which governs its traits (C) the chronological expression of its genes,
(D) the physical expression or its genotype (E) its adult form
14. In the current classification system, families are grouped into: (A) classes (B) phyla
(C) orders (D) divisions (E) kingdoms.
15. If you are looking at an organism that is eukaryotic, multicellular, heterotrophic and has
chitin in its cell walls, you are looking at a member of the Kingdom: (A) Protista (B) Fungi
(C) Archaeobacteria (D) Animalia (E) Plantae.
16. Viruses are assigned to: (A) Archaeobacteria (B) Protista (C) Eubacteria (D) Prokaryota
(E) None of the above.
17. In a co-evolutionary arms race, after a plant evolves a novel chemical defense against a
herbivore, (A) the herbivore can be expected to go extinct (B) the herbivore can be expected
to disperse to new habitats (C) the herbivore can be expected to evolve resistance to the
plant’s defence (E) the plant can be expected to outcompete all other plants in the same
environment
18. All viruses form _______ around their nucleic acid. (A) an envelope (B) a cell wall
(C) a capsid (D) a cell membrane (E) a capsule
19. People with sickle cell anemia have a mutation in the gene for the blood pigment hemoglobin
that carries oxygen.
The normal RNA sequence for hemoglobin is: CUG ACU CCU GAG GAG AAG UCU
The sickle cell RNA for hemoglobin is: CUG ACU CCU GUG GAG AAG UCU
This is an example of (A) nucleotide deletion (B) nucleotide substitution
(C) nucleotide addition (D) frameshift mutation (E) homeotic mutation
20. The type of mimicry in which a palatable species resembles a toxic species
(A) Mullerian (B) Batesian (C) diffuse (D) commensal (E) homotypy
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21. The principle of competitive exclusion states that (A) no two species can coexist unless they
are sharing the same resource (B) no two species can long coexist if they are sharing the
same limiting resource (C) if two species are sharing the same resource, one will always
go extinct (D) competition between two species always results in character displacement.
22. Which of the following is NOT a potential pre-zygotic reproductive barrier?
(A) temporal segregation of breeding seasons (B) differences in chemicals that attract males
(C) hybrid infertility (D) special segregation of mating sites (E) sperm that cannot penetrate
the egg
23. Which of the following is not a condition expected to favor allopatric speciation?
(A) Continents drift apart and separate previously connected lineages (B) A mountain range
separates formerly connected populations (C) Different environments on two sides of a
barrier cause populations to diverge (D) The range of a species is separated by loss of
intermediate habitat (E) Polyploid individuals arise in one part of the range of a species
24. In the process of transcription: (A) the base sequence of DNA is copied into RNA (B) a
polypeptide is formed as specified by the genes in chromosomes (C) rRNA is specified by
exons in DNA (D) a strand of mRNA is formed with base sequences complementary to
those of DNA (E) mRNA is formed as coded by introns.
25. Viruses are most conveniently thought of as: (A) lost chromosomes (B) the most primitive
bacteria (C) fragments of genomes (D) prions (E) escaped genomes.
26. In white tigers, the absence of fur pigmentation is caused by a recessive allele. This allele
also causes the tigers to be cross-eyed. If two tigers heterozygous for this allele mate and
produce offspring, what percentage can be expected to be white and/or cross-eyed?
(A) 25% will be white and the same 25% will be cross-eyed. (B) 25% will be white and
25% will be cross-eyed, but not necessarily the same 25% due to independent assortment.
(C) 50% will be both white and cross-eyed. (D) Because it is a recessive allele, none of the
offspring in the F1 generation will be white or cross-eyed.
27. Cell division in bacteria takes place mainly by: (A) conjugation (B) binary fission
(C) sporulation (D) fragmentation (E) mitosis.
28. What is the best criterion for determining if a trait is due to polygene inheritance?
(A) there are multiple alleles (B) it is pleiotropic (C) it has epigenetic effects
(D) it produces a normal distribution (bell shaped curve) of the trait
(E) the Punnett Square indicates that the genes sort independently, i.e are not linked.
29. Resource partitioning is the likely result of: (A) competitive exclusion (B) disruptive
selection (C) allopatric speciation (D) stabilizing selection (E) kin selection.
30. Which of the following is NOT something we would expect to find in a bacterium?
(A) plasma membrane (B) ribosomes (C) Golgi body (D) cell wall (E) RNA
31. In the equation p2 + 2pq + q2 which represents the Hardy-Weinberg equilibrium, what value
represents the recessive allele frequency in the gene pool? (A) p2 (B) 2pq (C) q2 (D) p (E) q
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32. Which characteristic would you expect the Protozoa to lack? (A) cell walls (B) rough
endoplasmic reticulum (C) heterotrophic nutrition (D) pseudopodia
(E) they would have them all
33. What is the best description of kin selection? (A) differential selection (B) animals who have
multiple siblings will survive better than those that don’t (C) close relatives are more fit than
distant relatives (D) brothers and sisters have a higher survival than cousins (E) individuals
will favor individuals that are closely related to them.
34. Which part of the flower ultimately matures into a fruit? (A) integument (B) ovary
(C) carpel (D) stamen (E) sepal
35. Which part of the human body, if any, is haploid? (A) spleen cells (B) skin cells (C) liver
cells (D) egg cells (E) none of the above
36. Which of the following would you not expect to find in single celled eukaryotic algae?
(A) Mitochondria (B) Ribosomes (C) Linear chromosomes (D) Chloroplasts
(E) I would expect all of the above
37. Cross-over is the: (A) the duplication of the double helix prior to cell division
(B) exchange of homologous chromosome segments (C) pulling apart of the chromatids
during meiosis (D) swapping of DNA units between prokaryotes and viruses. (E) none of the
above.
38. In epistasis (A) nothing changes from generation to generation (B) one gene alters the
effect of another (C) a portion of a chromosome is deleted (D) a portion of chromosome is
inverted (E) the behavior of two genes is entirely independent
39. What is the best way to describe genetic drift? Genetic drift: (A) is a gradual change in genes
(B) occurs when two populations interbreed (C) is adaptation to a habitat (D) occurs when it
is needed (E) is the change of a population’s genetic make-up through chance alone.
40. What is a polyploid number for a plant that has a diploid number of 12? (A) six
(B) ten (C) nineteen (D) twenty-four (E) none of the above
41. Two species of chipmunks live in the same forest. One of them breeds just after the spring
frost; the other breeds in early summer. The two populations appear to be examples of
(A) gametic isolation (B) behavioral isolation (C) ecological isolation (D) temporal
isolation (E) geographic isolation
42. A key difference between mitosis and meiosis is that: (A) mitosis leads to the transfer of
genetic information from generation to generation and meiosis does not (B) there is a
duplication of genetic material prior to cell division in one and not the other. (C) Diploid
cells are the result of the process in mitosis and haploid cells in meiosis (D) There are two
cell divisions in mitosis and one in meiosis (E) cross-over is common in mitosis but not
meiosis.
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43. Cladistic relationships are based upon: (A) similar use of unlike structures (B) dissimilar use
of similar structures (C) common lines of descent (D) analogous structures (E) epigenetic
effects.
44. What is characteristic of a retrovirus? (A) lacks a protein coat (B) infects plasmids
(C) always has an RNA genome (D) lacks an envelope (E) typically infects plants.
45. Which important condition must be fulfilled if two populations are to be considered different
species? (A) geographic isolation (B) reproductive isolation (C) lack of mutation in both
populations (D) disjunct distributions (E) presence of homologous structures
46. The function of tRNA is to: (A) provide a place for polypeptide synthesis (B) transport
amino acids to the ribosome (C) travel to the ribosome to direct the assembly of
polypeptides (D) transcribe DNA (E) translate DNA.
47. The drug AZT is very effective at treating AIDS patients and reducing the number or virions
present in the blood. Unfortunately, the effectiveness of this treatment rapidly diminishes
over time. How does HIV acquire resistance to AZT? (A) The HIV needs the resistance to
survive and mutates in response (B) AZT promotes the mutation of the HIV genome
(C) Some HIV have natural resistance and they survive and reproduce (D) HIV
overcomes the Central Dogma (E) All of the above
48. The concept of “Intelligent Design” to explain how organisms adapt, has been ruled
unconstitutional because: (A) organisms are not perfect (B) the presence of vestigial organs
cannot be explained by the argument (C) the “Intelligent Designer must necessarily be a
god (D) ontogeny recapitulates phylogeny which is incompatible with the concept (E) all of
the above.
49. Where would you not expect to find a cell wall? (A) jellyfish (B) mushroom (C) sunflower
(D) bacterium (E) all would have a cell wall
50. What is analogous to the human sperm in an angiosperm? (A) pollen (B) anther
(C) stamen (D) cotyledon (E) none of the above
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