Population Dynamics and Population Genetics Take Home Quiz COVID 2020

Biology 30 with Lake /31 /9 /35

Congratulations – you made it!! The End of the Biology 30 program – you may use your notes
and/or textbook to help you with these questions. Have fun!!

Multiple Choice – Read each question carefully and circle the answer that you think is the most
correct. Each question is worth one mark.

Use the following information to answer the next question.

The Amish are a group of people who rarely marry outside of their community. In one group of Amish in
Ohio, the incidence of cystic fibrosis was 19 in 10 816 live births. A second group of Amish in Ohio had no
affected individuals in 4 448 live births. No members of either group are related. These data illustrate what
population geneticists refer to as the “founder effect.”
—from Klinger, 1983

1. The “founder effect” seems to occur when

a. the environment favours one population over another population

b. a non-representative subpopulation forms the basis for an isolated population
c. individuals from one population move into and become part of a second population
d. two similar populations exist in the same community without being reduced in number

Use the following information to answer the next question.

The fathead minnow is a small fish common in Alberta waters and is used as a food source by many
different predators. When injured, some minnows secrete a chemical (called schreckstoff) that both attracts
predators and causes other minnows to huddle in large groups.
Approaching predators tend to be distracted by the mass of minnows and by each other.
Often, the injured minnow can escape.
—from Gonick, 1996
2. The frequency of the gene that controls the production of schreckstoff by minnows is likely

a. to increase in the gene pool of the population

b. to decrease in the gene pool of the population
c. to stay the same in the gene pool of the population because natural selection is occurring
d. to stay the same in the gene pool of the population because natural selection is not occurring

Use the following information to answer the next question.

A community of Pima Indians in the American Southwest has a very high rate of diabetes in their adult
population. Of the population of adults over the age of 35, 42% to 66% develop diabetes. The recessive trait
that causes diabetes in this population is a distinct disadvantage to individuals whose diets are rich in
carbohydrates.

Numerical Response #1: If 42% of the population have diabetes, then the percentage of the
population who are carriers is calculated to be __________%.

(Record your answer as a whole number)

 Use the following information to answer the next question.

In Drosophila (fruit flies), a gene called Sd (segregation disorder) has been discovered. In
heterozygous (Sd/sd) individuals, the Sd allele results in the destruction of gametes containing
the sd allele. Those gametes containing the Sd allele develop normally.

3. The gene pool of Drosophila is affected by the Sd allele because this allele

a. produces new gene combinations

b. increases genetic diversity
c. favours natural selection
d. increases in frequency

Use the following information to answer the next question.

In a randomly mating population of Drosophila, 4% of the flies have black bodies (an autosomal,
recessive trait) and 96% have brown bodies. This population is assumed to be in a Hardy-
Weinberg equilibrium.

4. If a researcher samples 10000 Drosophila from this population, the number of flies expected to
be homozygous dominant for body color is

a. 400
b. 3200
c. 6400
d. 9600
Use the following information to answer the next two questions.

The Ancon sheep has unusually short legs, which is an autosomal recessive trait. Through
progressive inbreeding of this strain of sheep, New England farmers were able to produce
sheep that are too short to jump the walls that enclose pastures.

5. Establishing a population of short-legged sheep from a single sheep that has short legs
illustrates the concept of

gene flow
succession
genetic drift
non-random mating

Numerical Response #2: If 36 sheep in a flock of 100 are Ancon sheep, then how many of the
sheep in the flock can be expected to be heterozygous for the Ancon trait?

Answer: __________

(Record your answer as a whole number)

6. During the last century, the chestnut blight fungus (Cryphonectria pasasitica), an introduced
species, decimated populations of the American chestnut tree (Castanea dentate). As a result, the
current populations of American chestnut trees have little genetic variation due to the

a. founder effect
b. gooseneck effect
c. Hardy-Weinberg effect
d. bottleneck effect

Use the following information to answer the next question.

Oculocutaneous albinism (OCA) is an autosomal recessive genetic disorder. People affected with
OCA have no pigment in their eyes, skin or hair because they are unable to produce normal
quantities of the pigment melanin. The frequency of OCA in Northern Ireland is 1 in 10000.

Numerical Response #3: What is the frequency of the carriers of OCA in the population in
Northern Ireland?

Answer: ___________

(Record your answer as a value from 0 to 1, rounded to two decimal places)

Use the following information to answer the two next questions.

Lactose intolerance is an autosomal recessive condition characterized by the inability to digest

lactose. People who are either homozygous for the dominant allele or heterozygous are able to
digest lactose. The frequency of lactose intolerance differs among populations. For example,
14% of northern Europeans have lactose intolerance.

Numerical Response #4: What is the frequency of the allele for the normal allele allowing
digestion of lactose in the northern European population?

Answer: _______________

(Record your answer as a value from 0 to 1, rounded to two decimal places)

 Use the following additional information to answer the next question.

The frequency of the dominant allele associated with the ability to digest lactose has increased
dramatically over time in the northern European population.

7. The dramatic increase in frequency over time of the dominant allele associated with the
ability to digest lactose provides evidence of

a. evolution in a population, which resulted from the selective advantage provided by the
dominant allele
b. evolution in the population, which resulted from the environmental resistance provided by
the dominant allele
c. genetic equilibrium in the population, which resulted from the selective advantage provided
by the dominant allele
d. genetic equilibrium in the population, which resulted from the environmental resistance
provided by the dominant allele

8. When limited food supplies have threatened to check human population growth, people have
used technology and social organization to clear forests, plow grasslands, grow crops, and
harness science to agriculture. This indicates that food is

a. a biotic factor that humans can manipulate

b. an abiotic factor that humans can manipulate
c. a biotic factor that humans cannot manipulate
d. an abiotic factor that humans cannot manipulate

Use the following information to answer the next five questions.

A group of ecologists have studied the Jasper National Park animal populations for many years
and have gather data related to aspects of its populations and the growth of these populations.

Use the following information to answer the next question.

In winter, snowshoe hares found in Jasper National Park create pathways in the snow between feeding and
resting sites. These travel lanes are then used by porcupines, making the porcupines’ movement through
deep snow easier.

9. What relationship exists between the snowshoe hare and the porcupine?

a. Mutualism
b. Predator–prey
c. Commensalism
d. Intraspecific competition
 Use the following additional information to answer the next question.
Data generated by ecologists working in Jasper National Park are used by park planners. Identifying a population as r-
selected or K selected may aid in wildlife management practices. Populations of caribou, elk and wolves have been
studied extensively.

Populations Characteristic Populations Descriptors

Offspring Number 1. Few Offspring

2. Large Numbers of Offspring
Body Size 3. Small in Size
4. Large in Size
Reproductive Maturity 5. Early reproductive maturity
6. Delayed reproductive maturity
Lifespan 7. Long lifespan
8. Short Lifespans

Numerical Response #5 : Identify the population descriptor, as numbered above, that best
matches each of the population characteristics below for a K-selected population such as the
caribou or elk.

Population Descriptor: _________ _________ _________ __________

Population Characteristic: Offspring Body Size Reproductive Lifespan
Number Maturity
(Record your four-digit answer in the space provided above)

Use the following information to answer the next question.

In areas where moose and caribou share habitat, they are both preyed upon by wolves. The population cycle
of the moose is affected by the presence of a second prey species, the caribou.

10. A reasonable prediction based on these predator–prey relationships is that

a. predator species would not show population changes caused by density-dependent factors
b. low numbers of caribou would cause wolf starvation if the moose population was also low
c. wolf and prey populations would decline as the same diseases spread through the three
populations
d. an area would have the same carrying capacity for moose as it has for caribou, even though
each species has different food preferences

Use the following additional information to answer the next two questions.

Many elk live in and around an 80 km2 area that includes the Jasper town site.

11. If a disease were to kill 90% of these elk (an epidemic), what would be the likely
consequence?

a. The genetic variability in the population would decrease.

b. The population’s resistance to all diseases would increase.
c. The mutation rate in genes for disease resistance would increase.
d. The population’s gene frequencies would return to pre-epidemic values through genetic drift.
12. The elk population of this area at the beginning of a study year was 500. If there were 35
births and 5 deaths throughout the year, what was the per capita growth rate for the elk
population during that year?

a. 0.03
b. 0.06
c. 6
d. 30

Use the following information to answer the next question.

Harbour porpoises living off the northeast coast of Scotland have been found dead washed up on shore, the
victims of violent, high-energy impacts. Zoologists have identified scratches on the dead porpoises that
match the teeth of an unlikely killer, the bottle-nosed dolphin, long assumed to be playful and gentle. These
two cetaceans (aquatic mammals), which share the same range and food supply, were thought to coexist
peacefully.
—from Discover, 1996

13. What type of relationship do the bottle-nosed dolphin and the harbour porpoise exhibit?

a. Symbiotic
b. Predator–prey
c. Intraspecific competition
d. Interspecific competition

Use the following information to answer the next three questions.

Pacific herring play a key role in the marine food web of Canada’s West Coast. They are prey fish and
comprise 30% to 70% of the summer diets of Chinook salmon, Pacific cod, lingcod, and harbour seals in
the coastal waters of southern British Columbia. The eggs of Pacific herring are important to the diets of
migrating sea birds, gray whales, and some invertebrates. Pacific herring are not mature enough to spawn
until age three. Spawning takes place in coastal areas where algae beds are abundant and the water is
uncontaminated.

14. Which of the following factors is an example of a density-independent factor that influences
Pacific herring survival and growth?

a. Algae populations
b. Ocean temperatures
c. Population of grey whales
d. Imposition of fishing quotas
 Use the following information to answer the next two questions.

The 42 000 wild horses and donkeys that live in the American West are reproducing at such a high rate that
they could severely damage range lands in the future. In an effort to prevent overpopulation, some mares
(females) are rounded up and injected with porcine zona pellucida (PZP), a long-lasting contraceptive. U.S.
Food and Drug Administration guidelines prohibit the use of PZP until after a wild mare has had at least
one successful pregnancy.
—from McInnis, 1996

15. Wild horses are considered to be a relatively K-selected species; however, one characteristic
exhibited by these wild horses that is similar to an r-selected species is

a. their large size

b. their relatively long lifespan
c. their relatively high reproductive potential
d. the large amount of parental care devoted to their offspring

16. Assuming that the contraceptive program manages the wild horse population successfully,
which of the following graphs would best represent the wild horse population growth curve
over time?
17. In the mid-1960s, a combination of intense fishing harvests and unfavourable ocean
conditions caused the Pacific herring population to decline drastically. Which of the following
rows shows the changes in relationships, after this decline, that were probably exhibited among
organisms that prey on the Pacific herring?

Row Interspecific Competition Intraspecific Competition

A. Decrease Decrease
B. Decrease Increase
C. Increase Decrease
D. Increase Increase

18. Salmon fishing is an important industry on the West Coast of Canada. If the salmon
population were to decrease because of overfishing, the Pacific herring population would
probably remain relatively stable if other predators showed which of the following changes?

a. Increased mortality and decreased emigration

b. Decreased mortality and increased emigration
c. Increased mortality and decreased immigration
d. Decreased mortality and increased immigration

Use the following information to answer the next question.

In Canada, to manage the harvest of fish, government departments issue quotas based on
population estimates. Problems in salmon and cod fisheries have drawn attention to problems
in the calculation of the estimates. Quotas based on these estimates have led to overharvesting
and have driven the cod fishery into disaster.

19. The carrying capacity for northern cod in Canada’s Atlantic region may be described as the

harvest quota that permits sustainable yield

harvest quota that matches the natural mortality of the cod
decline on a growth curve that shows the population size dropping
plateau on a growth curve that shows the population size has reached a limit

Use the following information to answer the next question.

Some grey whales have barnacles living on their backs. As the whales move from one location to
another, the barnacles are exposed to new sources of their food, plankton. Whales are unaffected
by the presence of the barnacles.

20. The relationship between the barnacles and the whales is one of

a. predation
b. parasitism
c. mutualism
d. commensalism
 Use the following information to answer the next question.

21. The process depicted by the above diagram illustrates

a. primary succession
b. random genetic drift
c. secondary succession
d. Hardy–Weinberg equilibrium

22. Which natural disturbance would most likely initiate primary succession in a certain area?

a. Land exposed when a glacier melted

b. An entire forest destroyed by disease
c. Natural vegetation removed by a flood
d. Grasslands burned by a lightning strike
 Use the following information to answer the next question.

Example of Ecological Relationships

1) Tropical acacia trees are hosts to a particular species of ants. The ants are provided with shelter
and nutrients from the trees. The trees are protected from other predatory insects by the ants.

2) The protozoan Opalina ranarum lives in the digestive tract of some frogs and obtains nutrients in
this way without harming the frog.

3) The protozoan Plasmodium is the cause of malaria. Plasmodium lives in the bloodstreams of
humans and reproduces inside red blood cells causing the red blood cells to burst.

Numerical Response #6: Match the ecological relationships, as numbered above, with the types
of symbiosis given below.

Ecological Relationship: __________ __________ __________

Type of Symbiosis: Commensalism Mutualism Parasitism

(Record your three-digit answer in the space provided)

Use the following information to answer the next five questions.

From 1968 to 1990, the population of snow geese nesting near Churchill, Manitoba, increased from
about 2 000 pairs (4 000 individuals) to about 22 500 pairs (45 000 individuals) with a nesting density
of around 1 000 nests per square mile. Snow geese winter along the coasts of Texas and Louisiana.
Prior to 1960, marshes along these coasts provided the main food sources (reeds, roots, and tubers) for
the geese. Destruction of these marshes and increased crop production of rice, corn, and soybeans has
occurred since that time. The stubble from these crops and spilled grains are easily obtained food
sources for the snow geese. Reduction in hunting and greatly increased food supplies from cultivation
near their wintering ground has cut mortality rates of snow geese in half over this period.

The high nesting density of the snow geese has left little foraging or nesting space for other species of
birds, and a decline in several duck species and shore birds has been observed.
Simultaneously, intensive foraging by the snow geese erodes and dries out patches of Arctic soil,
reduces regrowth of grasses and sedges, and greatly increases soil salinity.
—from Brodie, 1997

Numerical Response #7: Based on the information provided, what is the per capita growth rate
of the snow goose population between 1968 and 1990?

Answer: __________

(Record your answer rounded to one decimal place in the space above)
23. Prior to 1960, the winter food sources in the marshes controlled the growth of the snow
goose population. The available supply of reeds, roots, and tubers in the marshes was

a. an example of a community of climax species

b. an example of a community of pioneer species
c. a density-dependent limiting factor for snow geese
d. a density-independent limiting factor for snow geese

24. Given a further increase in the snow goose population, in the Churchill, Manitoba nesting
area

a. interspecific competition will increase because of decreased species diversity

b. interspecific competition will increase and intraspecific competition will decrease
c. intraspecific competition will increase because available food supplies are decreasing
d. intraspecific competition will decrease because fewer snow geese will be able to find nesting
sites

25. To preserve the diversity of this ecosystem, the first logical human intervention would be to

a. extend the hunting season and increase collection of snow goose eggs
b. replant or reseed grasses and sedges depleted by snow goose foraging
c. reintroduce the duck species and shore bird species that have disappeared from the coastal
marshes
d. prevent soil erosion by introducing plant species adapted to high salinity in order to anchor
the top soil

26. Based on the information provided, it would be reasonable to conclude that the snow goose
population

a. has increased its biotic potential

b. has a higher mortality than natality rate
c. is in the growth phase and environmental resistance is increasing
d. has reached the carrying capacity of the ecosystem and environmental resistance is
decreasing

Use the following information to answer the next two questions.

The Arctic National Wildlife Refuge in Alaska is home to many species of arctic animals,
including the Porcupine caribou herd. The calving grounds of the caribou constitute an area of
360 000 hectares in the wildlife refuge. The population of the Porcupine caribou on the calving
grounds decreased from 178 000 in 1989 to 129 000 in 2001.

Numerical Response #8: What was the population density of the Porcupine caribou herd on the
calving grounds of the Arctic National Wildlife Refuge during the calving season of 2001?

Answer: __________ (Place your answer in the space provided.)

27. What was the per capita growth rate of the Porcupine caribou herd between 1989 and 2001?

a. +0.38
b. +0.28
c. –0.28
d. –0.38

Use the following information to answer the next three questions.

Wood bison are the largest land animals in North

America. They were a major food source for people
of the First Nations. In the 1650s, an estimated 168
000 bison roamed northern Alberta, northeastern
British Columbia, and the Northwest Territories. By
1891, only 250 bison were left in these regions.

28. Prior to the 1650s, the wood bison population in North America remained close to the
carrying capacity of its habitat. The generalized growth curve and the reproductive strategy of
the wood bison were, respectively,

a. a J-curve and r selection

b. a J-curve and K selection
c. an S-curve and r selection
d. an S-curve and K selection

29. Hunting of the bison for meat and hides by First Nations people helped maintain the bison
population near the carrying capacity of its habitat by increasing the

a. natality of the bison

b. intraspecific competition
c. environmental resistance
d. biotic potential of the bison
 Use the following additional information to answer the next question.

Some Relationships Between Wood Bison and Other Species

1. Elk and deer compete with wood bison for food and living space.
2. Many wood bison are infected with tuberculosis or brucellosis bacteria.
3. Smaller wood bison compete with larger wood bison for food and living space.
4. Grazing by wood bison provides more suitable digging conditions for prairie dogs.

Numerical Response#9: Match each of the relationships numbered above with its classification,
as given below.

Relationship: __________ __________ __________ __________

Classification: Parasitism Commensalism Interspecific Intraspecific
competition competition

(Record all four digits of your answer in the space provided above)

Use the following information to answer the next two questions.

To study the effect of grazing on biodiversity in a grassland community, scientists prevented
sheep and rabbits from accessing a particular area of the grassland. They discovered that
biodiversity decreased in areas where grazing did not occur because grazing prevents the most
successful plant species from overtaking an area. When grazers consume successful plant species,
some of the less successful plant species are given a chance to grow.

30. Plant species that consistently remain in the grassland community where grazing is
prevented are known as

a. seral species
b climax species
c. pioneer species
d. intermediate species

31. Grazing increases biodiversity in a grassland by decreasing the

a. gene flow of less successful plant species

b. genetic drift of more successful plant species
c. interspecific competition for less successful plant species
d. interspecific competition for more successful plant species
Short Answer Portion – Read each question carefully and use the space provided to respond.
The value of each question is indicated in brackets.

1. After careful observation, you believe that two species occupy the same ecological niche in
the ecosystem you are studying. You find this hard to believe. First define the terms ecosystem
and niche and then explain how that organisms are able to exist with this situation. (3)

2. One fine day, you are out for a casual stroll when a strange piece of graffiti catches your eye
(see below ). In a flash of educational insight, you know that you can add to this piece of
classical art. Grabbing the discarded spray cans, you decide to add the following terms where
they belong: lag phase, exponential phase, stationary phase, biotic potential and environmental
resistance. You even go so far as to title the artwork and define one of the terms you have
added. Bravo!! (4)
3. As you are finishing your artwork, a random stranger walks by and asks you why you
missed a term and why the leveling off line is not correct. To save your piece of mind, you
formulate a quick explanation and write it in the space below. (2)

4. The great bunny explosion has happened again and community gardens are being affected
greatly, leading to a decrease in the health of these gardens. Identify whether the bunnies are a
density-dependent or density-independent factor and explain your choice. (2)

5. An individual fly has a mutation that allows it to survive being sprayed by an insecticide. Is
the mutation itself an example of microevolution? Justify your answer. (2)
6. Six out of 2400 babies that were born at a maternity hospital died shortly after birth from
colonic obstruction due to a recessive allele. (4)
a) Determine the frequency of the lethal allele in the population, expressed as a percent.
b) What percent of the population would you expect to be carriers of the lethal allele?
c) The population is closely knit and isolated. Explain why the incidence of infant mortality due
to the recessive lethal allele is relatively high.

7. Explain the concepts of the Law of Minimum and Shelford’s Law of Tolerance. (2)
8. The ten year cycles of the populations of the snowshoe hare and Canada lynx was first
recorded from fur returns of Hudson’s Bay Company traders in the late 1800’s. The cycles
revolve around the lynx’s preference for hares over other animals as a food source. This
predator-prey relationship has been much studied since this time.

a. In 1991, the lynx population in the MacKenzie Bison Sanctuary was 19 and in 1992 was 3. The
area of the sanctuary is 10000 km2. Calculate the density of the lynx population in 1991 and
1992. Show your work. (3)

b. Calculate the per capita growth rate for the lynx population from 1991 to 1992. Show your
work. (2)

c. The density of the snowshoe hare in the study area was about 800 km2 in 1990 and about 100
km2 in 1991. Identify one possible cause for the change in the lynx population density during
the 1991 to 1992 time period. (1)

d. After the decline in the hare population, younger male lynx where found to have migrated as
far as 500 km from the study area. Explain how the gene pool of the neighboring lynx
populations would be affected. (1)
9. You are attending an evening presentation on bighorn sheep and learn that they are usually
found on remote, rocky cliffs in the mountains. In the winter, they graze in lower mountain
pastures and then they move to higher alpine ranges in the spring. They are able to escape
predators such as mountain lions and wolves because of their well-developed abilities to climb
and jump in their rocky habitat. Between 1960 and 2002, the bighorn sheep populations of New
Mexico went from approximately 450 sheep to 130 sheep. State officials in New Mexico blame
the decline in the bighorn population on predation by mountain lions and have responded by
increasing the quote for hunting the mountain lions. A young person sitting next to you asks
you the following questions during and after the presentation.

a. Is the relationship between mountain lions and wolves an example of intraspecific or

interspecific competition and why? (2)

b. What was the growth rate of the bighorn sheep population between 1960 and 2002? (2)

c. Which condition(s) required for a Hardy-Weinberg equilibrium in the gene pool of the
mountain lion populations will be initially affected by increased hunting and why? (2)

10. Introduced species can have a cost, both economically and ecologically. Define what an
introduced species is and why it has the impact is does using a real life example. (3)