Download An explanation based on many lines of evidence, tested

BIO152 Term Test 1 10 of 10
1. A scientific theory is
a. An observation leading to a strong hypothesis.
b. A conjecture, idea or hypothesis of how something works or how it came to be.
c. An educated guess about something; it is the starting point to find the real answer.
d. An explanation based on many lines of evidence, tested in many ways, and
provides valid predictions.
2. Which of the following is NOT a feature of scientific hypotheses?
a. They make predictions.
b. They are based on observations.
c. They can be tested by experimentation.
d. They can be tested by observational analysis.
e. They are usually proven true.
3. What is a null hypothesis?
a. What should be observed in an experiment if a hypothesis is correct
b. A proposed explanation for a scientific phenomenon
c. An alternative possibility in the event that the explanation being tested
does not apply.
d. An experiment to test for factors that might influence an experiment’s
outcome
4. Identifying evolution in action: Identify which scenario described below is most
likely to NOT result in evolution.
a. Insecticide is applied to a population of mosquitoes; most of which are initially killed
upon exposure to the chemical; but a few survive and reproduce.
b. A man spends many hours in the gym exercising and is able to increase his body
weight, muscle mass, and strength, which makes him feel healthier.
c. Some male individuals in a population of kangaroos are born with larger front paws
and longer forearms. This gives them an advantage when boxing other males to
compete with them for mating with females.
d. Toxic levels of heavy metals are dumped as waste from coal mines. Initially, no
plants will grow on the waste dump; but eventually some grasses begin to colonize
the dump sites and reproduce.
e. A hurricane blows a small group of beetle-eating birds to an island in the ocean.
Although the new environment lacks the beetles that the birds normally eat, it has
various types of hard-shelled nuts. Some of the birds have larger, more pointed beaks
and are able to crack the nuts open.
October 2005
BIO152 Term Test 1 10 of 10
5. Limpets growing in the ocean in the intertidal zone where they experience heavy
wave action, are more conical than individuals of the same species growing in the
subtidal zone where they are protected from waves. Individuals moved from the high
intertidal zone to the subtidal zone, add new growth, which produces a flatter,
subtidal shape. This experiment suggest that the difference in shape is
a. Environmentally-induced and likely an example of acclimitization
b. Environmentally-induced and likely an example of natural selection
c. Due to genetic variation which will result in natural selection based on shape.
d. Cannot be answered without more information.
6. What is an important feature of sexual reproduction? Sexual reproduction
a. is unique to plants and animals.
b. produces variation through genetic recombination.
c. uses mitosis to produce gametes.
d. is more efficient than asexual reproduction.
e. is always associated with selective mating.
7.
Selection acts on ________ variation; however, evolution depends on ______
variation in the population.
a. phenotypic; genetic
b. genetic; phenotypic
c. genetic; environmentally-induced
d. environmentally-induced; phenotypic
e. environmentally-induced; genetic
8. Doctors have been treating patients infected with the organism that causes the disease
malaria with ZAPIT. However, they noticed that the effectiveness of ZAPIT has been
decreasing steadily for a number of years as the organism becomes more resistant to
the drug. This phenomenon is an example of what type of selection?
a. Stabilizing
b. Disruptive
c. Directional
d. No selection
9. Which one of the following predictions follows from the sexual selection hypothesis
for why giraffes have long necks?
a. In contests over females, the best-nourished male should always, or almost
always, win.
b. In contests over females, the male with the longest neck should always, or
almost always, win.
c. In natural populations, female neck length should decline over time.
d. Young males that are given extra amounts of high-quality food should grow
particularly long, strong necks.
October 2005
BIO152 Term Test 1 10 of 10
10. Which of the following statements describes similarities between natural and sexual
selection?
a. Individuals with certain variations have more surviving offspring.
b. Traits that are selected are beneficial to survival of both sexes; these traits
are genetic and inherited.
c. Selection operates on all individuals of the same species.
d. Selection operates on both sexes equally.
11. If a population is well adapted to its current environment, and if the environment
remains constant, what type of reproductive strategy will be most successful?
a. Sexual reproduction
b. Asexual reproduction
c. Both will be equally successful
d. Neither will be successful over long periods of time.
12. For a biologist studying a small fish population in the lab, which Hardy-Weinberg
condition is easiest to meet?
a. no selection
b. no genetic drift
c. no gene flow
d. no mutation
e. random mating
Question 13 & 14
Researchers studying a small milkweed population note that some plants produce a toxin
and other plants do not. They identify the gene responsible for toxin production. The
dominant allele (T) codes for an enzyme that makes the toxin, and the recessive allele (t)
codes for a nonfunctional enzyme that cannot produce the toxin. Heterozygotes produce
an intermediate amount of toxin. The genotypes of all individuals in the population are
determined (see chart) and used to determine the allele frequencies in the population.
Genotype Frequencies
TT
Tt
tt
0.64
0.32
0.04
(expected)
0.64
0.32
0.04
Allele Frequencies
T
t
0.8
0.2
13. Is this population in Hardy-Weinberg equilibrium?
a. yes
b. No; there are more heterozygotes than expected.
c. No; there are more homozygotes than expected.
d. More information is needed in order to answer this question.
October 2005
BIO152 Term Test 1 10 of 10
14. The researchers had already noted that negligible mutation and migration existed in
this milkweed population, and the butterflies that pollinate these plants are not
affected by the toxin. Which of the following would be a logical conclusion about this
milkweed population based on your answer to the question above?
a. There is little of no genetic drift or selection.
b. There is either a heterozygote advantage or inbreeding depression.
c. There is either directional selection or sexual selection.
d. There is either disruptive selection or genetic drift.
e. There is either stabilizing selection or gene flow.
15. Currently the only predators of Galápagos marine iguanas are Galápagos hawks.
Iguana body size is not correlated with risk of hawk predation, although small iguanas
can sprint faster than large iguanas. If predators (e.g., cats) that preferably catch and
eat slower iguanas are introduced to the island, iguana body size is likely to
__________ in the absence of other factors; the iguanas would then be under
__________ selection.
a. increase; directional
b. increase; disruptive
c. decrease; directional
d. decrease; stabilizing
e. stay the same; stabilizing
16. Three-spined stickleback fish (Gasterosteus aculeatus) show substantial heritable
variation in gill raker length. Fish caught in open water tend to have longer gill rakers
and eat different foods than do those caught in shallower water. Longer gill rakers
appear to function better for capturing open-water prey, while shorter gill rakers
function better for capturing shallow-water prey. Which of the following types of
selection is most likely to be found in a lake with a high density of these fish?
a. directional selection
b. stabilizing selection
c. disruptive selection
d. sexual selection
e. no selection
17. Male turkeys have a snood, which is a flap of skin that hangs across their beak. Snood
length is negatively correlated with parasite load (e.g., males with longer snoods have
fewer parasites), and females prefer to mate with long-snooded males. This is an
example of:
a. the fundamental asymmetry of sex
b. sexual selection via female choice
c. sexual selection via male-male competition
d. a genetic marker
October 2005
BIO152 Term Test 1 10 of 10
18. In some jacana species, males take care of the eggs and young, and females compete
for territories against one to several males. Female jacanas are significantly larger
than males. Which of these statements would you predict to be true of this bird
species?
1.Male jacana fitness is primarily limited by ability to take care of eggs and raise young.
2.Female jacana fitness is limited by the number of males with which they can mate.
3.Variation in reproductive success should be greater in male jacanas than in females.
4.Variation in reproductive success should be greater in female jacanas than in males.
5.Males and females have equal variation in reproductive success.
a.
b.
c.
d.
e.
1 and 3
2 and 4
1, 2, and 3
1, 2, and 4
5
19. Male reproductive success, measured as the number of offspring surviving to
adulthood (pupating), is found for two closely related beetle species and graphed
below. Which of these statements would you expect to be true of sexual dimorphism
in the two species?
a.
b.
c.
d.
Species A should have greater sexual dimorphism than species B.
Species B should have greater sexual dimorphism than species A.
Species A and B should have about equal amounts of sexual dimorphism.
Neither species should show any sexual dimorphism.
20. In 1986 a nuclear power accident in Chernobyl, USSR (now Ukraine) led to high
radiation levels for miles surrounding the plant. The high levels of radiation caused
elevated mutation rates in the surviving organisms, and evolutionary biologists have
been studying rodent populations in the Chernobyl area ever since. Based on your
understanding of evolutionary mechanisms, which of the following most likely
occurred in the rodent populations following the accident?
a. Mutation by itself led to major changes in rodent physiology over time.
b. Genetic drift followed by mutation led to increased genetic variation.
c. Mutation caused genetic drift and decreased fitness.
d. Mutation caused the fixation of new alleles.
October 2005
BIO152 Term Test 1 10 of 10
21. Guppies are small fish found in streams in Venzuela. Male guppies are brightly
coloured, but the amount of colouring varies depending on the number and types of
predators in the ponds. If female guppies prefer to mate with males having colourful
body patterns despite the risk of predation for colourful males, what hypothesis (es)
would best explain the continuation of bright colouration in the males?
a. Changing environment hypothesis
b. Natural selection
c. Bad gene hypothesis
d. Good genes
e. All of the above
f. a and d
g. b and c
22. In what sense is the Hardy-Weinberg principle a null hypothesis, similar to the
control treatment in an experiment?
a. It defines what genotype frequencies should be if nonrandom mating is
occurring.
b. Expected genotype frequencies can be calculated from observed allele
frequencies and then compared with the observed genotype frequencies.
c. It defines what genotype frequencies should be if natural selection, genetic
drift, gene flow, or mutation is occurring and if mating is random.
d. It defines what genotype frequencies should be if evolutionary
mechanisms are not occurring.
October 2005
BIO152 Term Test 1 10 of 10
23. Which of these statements most fully characterizes the fundamental asymmetry of
sex?
a. Female fitness is limited most by the ability to get resources for producing
eggs and rearing young, while male fitness is limited by the ability to
attract females.
b. Female fitness is limited most by the ability to attract males, while male
fitness is limited by the ability to get resources for provisioning the female.
c. Female fitness is limited most by the ability to get resources for producing
eggs and rearing young, while male fitness is limited by the ability to get
resources for provisioning the female.
d. Female fitness is limited most by the ability to attract males, and male fitness
is limited by the ability to attract females.
24. Which of the following is NOT true about sexual selection and its consequences?
a. In a species with strong sexual selection, female choice of mates benefits her
ability to survive and the ability of her offspring to reproduce.
b. Bright colours and extravagant ornaments in males are often the result of
natural selection.
c. Sexual dimorphism tends to be absent when there is no competition for mates
among members of the same sex.
d. Sexual dimorphism cannot be easily explained by ordinary natural selection
because males and females of a species generally face the same environmental
conditions.
e. Females are generally expected to be choosy about the males they mate with.
25. Recall the chili pepper experiment that tested whether capsaicin acts as a deterrent to
predators. What was the rationale for studying the eating habits of the curve-billed
thrasher—a known seed disperser?
a. The thrasher should eat mild and hot chilies in order for the chilies’ seeds
to be dispersed.
b. The thrasher should eat only the mild chilies, because the hot ones could cause
damage to its mouth.
c. The thrasher should eat only the hot chilies, because it is capable of finding
water very quickly.
d. The thrasher should not eat any of the chilies, because it would destroy the
chilies’ seeds.
October 2005
BIO152 Term Test 1 10 of 10
The following experiments are used for questions 26–28:
In 1668 Francesco Redi did a series of experiments on spontaneous generation. He began
by putting similar pieces of meat into eight identical jars. Four jars were left open to the
air, and four were sealed. He then did the same experiment with one variation: instead of
sealing four of the jars completely, he covered them with gauze (the gauze will exclude
the flies while allowing the meat to be exposed to air). In both experiments, he monitored
the jars and recorded whether or not maggots (young flies) appeared in the meat.
26. What hypothesis was being tested in the initial experiment with open versus sealed
jars?
a. Spontaneous generation is more likely during the long days of summer.
b. The type of meat used affects the likelihood of spontaneous generation.
c. Maggots do not arise spontaneously, but from eggs laid by adult flies.
d. Spontaneous generation can occur only if meat is surrounded by air.
27. In both experiments, flies appeared in all of the open jars and only in the open jars.
Which one of the following statements is correct?
a. The experiment was inconclusive because Redi used only one kind of meat.
b. The experiment was inconclusive because it did not run long enough.
c. The experiment supports the hypothesis that spontaneous generation occurs in
rotting meat.
d. The experiment supports the hypothesis that maggots arise only from
eggs laid by adult flies.
28. Redi’s first experiment compared maggot appearance in jars which were open and
sealed with a cover. His second experiment compared open and gauze-covered.
Which of the following statements is NOT a reasonable, plausible hypothesis for
what is being tested in the second experiment.
a. Adult flies are attracted to rotting meat by the smell.
b. Maggots can appear in rotting meat only if they are protected from predatory
wasps.
c. If maggots do not appear in sealed jars, it is because they require fresh air to
grow.
d. Maggots can appear in the rotting meat if the jars are not sealed correctly.
29. What does the biological term evolution mean?
a. The strongest individuals produce the most offspring.
b. The characteristics of an individual change through the course of its life, in
response to natural selection.
c. The characteristics of populations change through time.
d. The characteristics of species become more complex over time.
October 2005
BIO152 Term Test 1 10 of 10
30. Which of the following is a condition needed for natural selection to occur?
a. Random mating must occur.
b. The population must be large for natural selection to occur.
c. Humans select which individuals mate.
d. Individuals within a population vary in their characteristics.
31. Which of the following explanations for change correctly expresses natural selection
as the process for evolution.
a. The widespread use of DDT in the mid-1900s put pressure on insect
populations to evolve resistance to DDT. As a result large populations of
insects today are resistant to DDT.
b. Wide-scale use of DDT in the mid-1900s selected for any insects that
carried the genes that made them resistant to DDT. These insects mated
and passed on their resistance to their offspring
c. Both statements are equally correct.
d. Neither statement correctly explains insect resistance to DDT by natural
selection.
32. Which of the following explanations for change correctly expresses natural selection
as the process for evolution.
a. Dinosaurs became extinct because they couldn’t evolve fast enough to deal
with climatic changes that affected their food and water supplies.
b. Dinosaurs became extinct because their physiological and behavioural
traits were too specialized and lacked enough variability to survive rapid
changes.
c. Both statements are equally correct.
d. Neither statement explains dinosaur extinction by natural selection.
Questions use Table 1 below
Table 1 Comparison of male cat traits and their offspring
NAME
Tabby
Chessy
Tony
Size
5 kg
4.8 kg
3 kg
# kittens
fathered
19
25
20
# Kittens
surviving to
15
14
14
adulthood
Age at
death(years)
13
16
12
Comments
Largest &
Mated with the Lost on family
strongest
most females
vacation; lived
on the street 2
more years
October 2005
Tiger
4 kg
20
19
9
Died from
infection after
cat fight
BIO152 Term Test 1 10 of 10
33. Which cat contributed the most genes to the next generation?
a. Tabby
b. Chessy
c. Tony
d. Tiger
e. Cannot be answered without more information.
34. Which cat is the “fittest” in evolutionary terms?
a. Tabby
b. Chessy
c. Tony
d. Tiger
e. Cannot be answered without more information.
35. What is the key point in Darwin’s explanation of evolution by natural selection ?
a. The biological structures most likely inherited are those that have become better
suited to the environment through constant use.
b. Mutations that occur are those that will help future generations fit into their
environments.
c. Slight variations among individuals significantly affect the chance that a
given individual will survive in its environment and be able to reproduce.
d. Genes change in order to help organisms cope with problems encountered within
their environments.
e. Extinction is nature’s way of weeding out undeserving organisms.
October 2005