Download Key for Exam 1 Part 1 - Evolutionary Biology

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This exam is worth 50 points
in the whole course
Evolutionary Biology
Exam I, 2016
You may take this part
of the exam with you
A. Multiple Choice Questions. Choose the best possible answer. Use the bubble sheet. (1 pt.
each)
1. An evolutionary tree is also called (A) phrenology (B) a dendrology (C) an endogeny
(D) a phylogeny (E) an ontogeny.
2. What is an example of inductive reasoning? (A) The population of the USA is over 300
million. (B) I measured the body temperature of hundreds of Mexican free-tailed bats
and concluded that they do not hibernate. (C) Webster’s dictionary says that birds are
warm blooded, have feathers and wings. Archaeopteryx is a fossil vertebrate and has wings &
feathers. Based on the definition, I would guess that it probably was warm blooded.
(D) Planets have an elliptical orbit; they are round in shape and are large. Pluto has these
characteristics and so it is a planet. (E) None of the above.
3. Natural selection is notoriously hard to see in nature, yet Darwin made it a linchpin in his
argument for evolution. What was the most compelling argument he offered for Natural
Selection being the causative agent for evolution? (A) He argued by analogy from the
effects of artificial selection by farmers. (B) He was emulating the argument from his
illustrious grandfather Erasmus Darwin who first stated the theory in his writings. (C) He
took his clue from Lamarck who first suggested the first scientific hypothesis of evolution.
(D) He believed the proposal of Thomas Malthus of struggle for existence. (E) He believed
the creationist arguments could not be tested and thus were not scientific.
4. Which statement is not part of Darwin’s hypothesis of evolution? (A) Survival of the fittest.
(B) Mutation causes variation (C) Populations tend to over-breed. (D) New species develop
because of changes in the environment causes natural selection (E) All of the above are part
of his hypothesis.
5. Did Darwin focus on the problem of the origin of life in his origin of species? (A)Yes, he
considered a variety of ideas. (B) Yes, he thought that life originated from chemicals here on
Earth. (C) Yes, he thought life originated in hydrothermal vents. (D) Yes, he realized that
organic molecules were occasionally found in meteorites and thought that the first forms
might have come from other planets. (E) No, he didn’t focus on it.
6. Which of the following predictions about fossils would one most reasonably make if the
creationist hypothesis were correct? (A) Large fossils should be in the lower rock strata
because they would sink faster in the sediments. (B) There would be no particular order to
the fossils. (C) Older rocks would have fewer modern species than younger strata.
(D) Complex organisms would appear in the deepest sediments. (E) None of the above.
7.
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.
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8. Which of the following statements is a prediction? (A) Watson and Crick said that DNA was
helical (B) If I use an infra-red camera, I will be able to visualize the dragon in the
basement (C) whales use their tail flukes to power their swimming (D) squid probably use
jet propulsion to power their locomotion. (E) None of the above.
9. Which of the following groups is considered to be the most immediate ancestor of reptiles,
including the flying reptiles such as pterodactyls? (A) amphibians (B) fish C) worms
(D) mammals (E) birds
10. How many heart chambers should we expect that Archaeopteryx to have? (A) one (B) two
(C) three (D) four (E) five
11. Radioactive dating puts the age of the earth at (A) 6,000 years ago (B) 10,000 years ago
(C) 28 million years ago (D) 13.7 billion years ago (E) none of the above
12. What kind of fossil is used to claim that living organisms lived on earth at least 3.8 billion
years ago? (A) permineralized fossil (B) carbon film fossil (C) cast of a fossil
(D) trace fossil (E) chemical fossil.
13. Darwin and Lamarck’s views of evolution primarily differed in regard to (A) change over
time (B) acquired characteristics (C) that natural selection was involved (D) genes were
the factors that determined variability (E) new species were formed over time
14. 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)
15. The reason that the dorsal fin of sharks and whales can not be homologous is that they do
(A) not have exactly the same external structure (B) they do not have exactly the same
internal anatomy (C) they are not derived from the same embryonic tissue (D) they do not
function exactly in the same way (E) their common ancestor didn’t possess a dorsal fin
16. Which of these structures are most likely to be considered analogous or homoplasic? (A) the
fingernails of a baboon and the claws of squirrel (B) the wings of a pterodactyl lizard and the
front legs of a dog (C) the stem of a rose bush and the tree trunk of an redwood tree (D) heart
of an artichoke flower and the heart of a lobster (E) quills on a porcupine and the spines on
a cactus
17. 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
18. Which of the following is not an eukaryote? (A) mushroom (B) sea weed (C) sea gull (D) sea
turtle (E) all are eukaryotes
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19. Gram negative bacteria do (A) stain with a Gram stain (B) not have mitochondria (C) lack
phospholipid membranes (D) have peptidoglycan (E) none of the above
20. Which of the following would be absent in prokaryotes? (A) thyamine (B) chlorophyll
(C) uracil (D) plasmids (E) all would be present
21. Which of the following represents a monohybrid cross between a homozygous recessive and
a heterozygote? A) Tt x Tt (B) ttmm x TtMm ( C) tt x Tt (D) ttmm x TTMM (E) none
of the above
22. 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%
23. Blue eyes (b) are recessive to brown (B). Suppose 2 parents had 11 children: 6 with blue and
5 with brown. Which of these statements is most likely to be right? (A) Both parents had blue
eyes. (B) One parent had blue & the other was homozygous dominant (C) Both parents had
brown eyes. (D) One parent had blue & the other was heterozygous (E) Both parents were
heterozygous.
24. Which of the following pairs of crosses results in the same phenotypic ratios?
(A) Aa x Aa and AA x aa
(B) AA x aa and AA x Aa
(C) AA x Aa and Aa x aa
(D) AA x aA and aa x aa
(E) None of the above
25. According to J.K. Rowling wizards & witches can be born from pure bloods or muggles.
Suppose the wizard/witch trait is recessive (m) and the muggle trait is dominant (M)
Hermione is a witch born of muggle parents. If her parents had another child what are the
chances that that one also would be a wizard or witch? (A) 0% (B) 25 (C) 50% (D) 75%
(E)100%
26. 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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27. Each of our chromosomes are composed of two chromatids joined by a centromere.
(A) These chromatids make up a diploid chromosome. (B) The cell that contains these sister
chromatids must be diploid. (C) The sister chromatids were formed by replicating a
single chromatid. (D) The sister chromatids were joined by fertilization, bringing together a
maternal and paternal chromatid.
28. What happens after Meiosis I? (A) Four cells have been produced. (B) The cells are
haploid.(C) The DNA will be replicated once more. (D) The cells are ready to perform as
gametes. (E) Each chromosome consists of a single strand of DNA.
29. During Meiosis crossover occurs (A) during DNA replication (B) as the sister chromatids are
joined by fertilization, bringing together a maternal and paternal chromatids. (C) during
Metaphase I when sister chromosomes line up. (D) very early in Meiosis II as the
chromosomes are lining up again. (E) late in Meiosis II just as the chromosomes are being
pulled apart.
30. Which statement about mitosis is not true? (A) A single nucleus gives rise to two identical
daughter cells (B) The daughter nuclei are generally identical to the parent nucleus (C) the
centromeres separate at the onset of anaphase. (D) Homologous chromosomes synapse in
prophase (E) The centrosomes organize the microtubules of the spindle fibers
31. Which statement is true about cytokinesis? (A) In animals a cell plate is formed (B) In
plants, it is initiated by furrowing of the membrane (C) It follows mitosis (D) In plant cells,
actin and myosin play an important role (E) It is the division of the membrane
32. The number of daughter chromosmomes in a human cell in anaphase II of meiosis is
(A) 2 (B) 23 (C) 46 (D) 69 (E) 92
33. In humans, spotted teeth are caused by a dominant sex-linked gene. A man with spotted
teeth whose father had normal teeth marries a woman with normal teeth. Therefore: (A) all of
their daughters will have normal teeth (B) all of their daughters will have spotted teeth (C)
all of their children will have spotted teeth (D) half of their sons will have spotted teeth (E)
all of their sons will have spotted teeth.
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34. Which of the following is not a difference between RNA and DNA? RNA has uracil and
DNA has thymine (B) RNA has ribose and DNA has desoxyribose (C) RNA has five bases
and DNA has four (D) RNA is a single strand polynucleotide and DNA is a double strand
(E) RNA molecules are smaller than chromosomal DNA molecules
35. In the double helix of DNA, what belongs on the complimentary DNA strand opposite
adenine? (A) thyamine (B) adenine (C) cytosine (D) guanine (E) uracil
36. Which statement about RNA is not true? (A) Transfer RNA functions in translation (B)
Ribosomal RNA functions in translation (C) RNAs are produced by transcription
(D) Messenger RNAs are produced on ribosomes (E) DNA codes for mRNA, tRNA and
rRNA.
37. Linked genes (A) must be immediately adjacent to one another on a chromosome (B) have
alleles that assort independently of one another (C) never show crossing over (D) are on the
same chromosome (E) always have multiple alleles
38. The genetic sex of a human is determined by (A) ploidy, with the male being haploid
(B) The Y chromosome (C) X and Y chromosomes, the male being XX (D) the number of
X-chromosomes, the male being XO (E) Z and X chromosomes, the male being ZZ
39. 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
40. Why are the chromosome numbers in animals usually even numbers? (A) because they
received one haploid set from each parent (B) because mitosis could not proceed with odd
numbers (C) because meiosis could not proceed with odd numbers (D) because the
chromatids are always double (E) none of the above
41. “Intelligence” and skin color are two examples of continuous variation in humans, whereas in
Mendel’s pea plants the purple allele was dominant over the white with no intermediates.
Which is the best explanation for the differences described above? (A) The seeds coding for
intermediate flower color are aborted within the seed pod and thus never develop (B) The
seeds coding for intermediate flower color have deleterious alleles that prevent them from
germinating (C) These variations in human are affected by lack of dominance in the alleles
that control these traits (D) Humans are more advanced than pea plants, so the genetics of
peas is much simpler that in humans (E) Many genes rather than one gene for a
characteristic control some variations in species
42. When two alleles actually both determine the condition of a trait such as in blood type AB,
we call this (A) co-dominance (B) incomplete dominance (C) multiple alleles (D) polygene
inheritance (E) epistasis
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43. Mother and father both find the taste of a chemical called phenylthiourea (PTU) very bitter.
But two of their four children find the chemical is tasteless. From the information provided,
what can you conclude? (A) the ability to taste PTU is a dominant trait (B) the inability to
taste PTU is a dominant trait (C) the ability to taste PTU is a recessive trait (D) PTU is
inherited as a semirecessive condition (E) PTU is a codominant allele
44. Here is a tree showing the evolution of circle, square, and triangle traits. The shapes indicate
the traits and the numbers (1-4) indicate common ancestors. Which trait displays homoplasy?
A) circle B) square C) triangle D) none of the above
45. What is the most recent common ancestor of A and D? (A) 1 (B) 2 (C) 3 (D) 4
46. Who is the closest living ancestor to organism E? (A) organism C; (B) organism D;
(C) organism A; (D) organisms C and D; (E) all organisms are equally closely related to
each other as they are all on the same time line.
47. Which organism is considered to be to be the most recent common ancestor to species A and
B? (A) 1 (B) 2 (C) 3 (D) 4
48. A species of bird eats a certain species of worm. This worm species can vary in size. It can
be large, medium, or small. The diagram below shows the percent survival of each worm
size. What size is being selected for most strongly (in other words, what worm size has the
highest fitness value? (A) small worms (B) medium worms (C) large worms (D) the bird
(E) fitness value does not anything to do with survival statistics.
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49. If the above scenario continues for several generations, what kind of selection seems to be
occurring? (A) stabilizing (B) differential (C) phylogenetic (D) disruptive (E) none of the
above
50. Using the table below: what will be the DNA code for aspartic acid? (A) CTG;
(B) GTG; (C) UGG; (D) GTA; (E) none of the above
RNA codons