Name: Biology

__________________________________________________ 30- _____

St. Mary’s
High School

Population Biology Unit Exam

Instructions: You may write / do rough work in the question booklet.

Record your answers on answer card(s) provided
1. The production of new genes or changes in allele possibilities is a result of:
a. Gene Flow
b. Genetic Drift
c. Mutation
d. Adaptation

2. In a population in which 1% has sickle-cell anemia ( an autosomal recessive disorder),

What percentage of the population should theoretically be carriers for the trait?
a. 81%
b. 22%
c. 43%
d. 18%

3. Which of the following terms is NOT characteristic of human populations in developed

countries?
a. Low Fecundity
b. r- selected species
c. S – shaped growth curve
d. Clumped Distribution

4. Which characteristic(s) are typical for a prey population:

a. Is adapted to escape the predator
b. Is larger in biomass than a predator population
c. Has a particular niche
d. All of the above

5. Once speciation has occurred:

a. Gene flow ceases
b. Reproductive isolation exists
c. Two species exist
d. All of the above

Use the following information to answer the next question

In a population 36% of the individuals have the homozygous dominant genotype.

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6. What proportion of the gametes in this population contain the recessive gene?
a. 60%
b. 16%
c. 40%
d. 64%

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Numerical Response # 1

Use the following information to answer the next question

Data generated by ecologists working in Jasper National Park is used by park planners in an
attempt to aid wildlife management. One of the initial studies performed assists park planners
with identifying a population as r-selected or K- selected. . Park planners have categorized
various population characteristics qualitatively based on acceptable quantitative ranges to
categorize some of the species they are studying. Some of the species studied extensively in this
program include caribou, elk and wolves.

Population Characteristic Qualitative Population 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

Life Span 7. Long Lifespan

8. Short Lifespan

Identify the qualitative 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 shown below

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 Elk Caribou

Qualitative 1 4 6 7
Population
Descriptor

Population Offspring Body Reproductive Lifespan

Characteristic Number Size Maturity

(Record your answer in the NR section of your answer card in the order of population
characteristics listed above)

7. Many Elk live in and around an 80km2 area that includes Jasper town site.
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 disease 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.

8. All of the following are mechanisms that lead to reproductive isolation except:
a. Temporal differences in breeding season between two populations.
b. Differences in food niches between two species.
c. Hybrid sterility
d. Mechanical incompatibility of genitalia
e. Complex courtship behaviour

Use the following information to answer the next question.

One of the components of Charles Darwin’s Theory of Natural Selection is referred to as
Survival of the Fittest. In this case those with the most advantageous adaptations for

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 their environment will have the best chance of survival and the best opportunity to pass
on their advantageous adaptations to the next generation.

9. The best measure of Darwinian ‘fitness’ of a given genotype is:

a. The length of time its possessor lives.
b. The number of heterozygous allele pairs it contains.
c. How rapidly it can find food.
d. How many of its offspring will survive to reproduction
e. How early it can begin reproduction.

Numerical Response # 2
Use the following information to answer the next question
Stages in the Development of an Area

1. This stage in a community’s development is when environmental conditions are such

that a predominant species of vegetation is maintained.

2. Pioneer plants such as lichens, grasses, and herbs are joined by shrubs and small trees
within two or three years. Years later larger trees are present and soil has
accumulated.

3. Lichens and grasses are found growing on a rock slide

4. Herbaceous and shrubby plants begin to grow in an abandoned field.

Match the above descriptions with the best stage or definition given below.
Description / 2 3 4 1
Stage

Definition Succession Primary Secondary Climax

Succession Succession Community

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 (Record your 4 digit response in the NR section of your answer card)

Use the following information to answer the next 7 questions

Ecologists did a population sampling of Richardson Ground Squirrels (gophers) in a

250 hectare (ha) field region in Kananaskis Country Alberta from 1980 to 1989.
The results of their sampling are shown (to two decimal places) in the following chart.

YEAR 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989

POPULATION 14.0 42.00 85.00 115.0 132.00 115.00 115.0 80.00 109.0 110.00
0 0 0 0

Richardson Ground Squirrel

10. Calculate the density per hectare of the gopher population in 1986 based on the sampling.
a. 0.46 gophers / ha
b. 20.00 gophers/ ha
c. 3.13 gophers / ha
d. 80.00 gophers / ha
11. The growth rate and per capita growth rate respectively of the gopher’s between 1980-
1989 is:

Growth Rate Percapita Growth Rate

a. 6.86 gophers / year 10.67

b. 10.67 gophers / year 6.86

c. 13.11 gophers / year 8.43

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 d. 8.43 gophers / year 13.11

12. Estimate the Carrying Capacity of the gophers in this field.

a. 14
b. 115
c. 132
d. 80

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 13. During which year could the numbers be explained by a predator species discovering the
gopher population in the field?
a. 1983
b. 1984
c. 1985
d. 1987
14. During which time period did exponential growth occur?
a. 1980 – 1982
b. 1980 – 1984
c. 1984 – 1987
d. 1985 – 1989

Numerical Response # 3
Use this additional information to answer the next question
Common Predators of the Richardson Ground Squirrel in Kananaskis Country

Predator Number of Predators (number per

100km2)

Coyote 0.6

Hawks 6.2

The size of the Coyote population in an area of 6000 km2 of Kananaskis Country is calculated to
be _____36_____ Coyotes.
(Record your answer as a whole number in the NR section of your answer card)

Use the following additional information to answer the next question

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 A growth curve was created using the data and extrapolated to project the anticipated
population numbers through to 1994; given no unpredictable environmental conditions
occur.
15. Which of the following growth curves below best illustrates the population of gophers
from 1980 through to a projected 1994 population?

150
100
Gophers

50
0 Growth Curve A

Time (years)

150
100
Gophers

50
0 Growth Curve B
80 82 84 86 88 90 92 94
19 19 19 19 19 19 19 19
Time ( years)

150
100
Gophers

50
0 Growth Curve C

Time ( years)

120
80
Gophers

40
Growth Curve D
0
80 82 84 86 988 990 92 94
19 19 19 19 1 1 19 19
Time ( years)

Use the following information to answer the next 2 questions

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16. The oscillations ( fluctuations) in the predator-prey populations primarily occur because:
a. An increase in the prey population will increase the predator population
indefinitely.
b. An increase in the prey population will allow for an increase in the predator
population until the prey population is reduced.
c. An increase in the predator population causes and immediate increase in the prey
population.
d. Of seasonal population densities.

Use the following additional information to answer the next question

In the winter of 1930, a toxic chemical, fatal to the prey but not to the predators,
was introduced into the environment.
17. The result on the predatory population will be:
a. Minimal as the chemical has no effect on the predators.
b. A drop in numbers due to the decreased availability of food.
c. A rise in numbers as there is now a lack of competition.
d. No change as the populations are not connected.
18. Succession in a system operates at the:
a. Population level
b. Community level

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 c. Level of Individual Organisms
d. Biome Level
19. When individuals from a population migrate to an area of another population of the same
species and begin interbreeding, this situation is most likely called:
a. Genetic Drift
b. Gene Flow
c. Speciation
d. Directional Selection
20. When the pattern of organisms is affected by abiotic factors, the distribution is said to be:
a. Clumped
b. Dispersed
c. Random
d. Uniform
Use the following information to answer the next question

Present Population Size 1000 individuals

Mortality Rate 130 individuals / year

Natality Rate 200 individuals / year

Immigration Rate 50 individuals / year

Emigration Rate 80 individuals / year

21. What will the population size be two years from now given the information above?
a. 1040 individuals
b. 1080 individuals
c. 1140 individuals
d. 1500 individuals

Use the following information to answer the next question.

Weeds, insect pests and disease result in a loss of about 45% of the world’s food
supply annually. The use of insecticides and herbicides reduces the loss of food
supply.
The most serious drawback of using chemicals to control pests is that most pest
populations, especially insects, develop genetic resistance to chemicals.

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22. How do insect populations develop this resistance described above and pass it on to
offspring?
a. Mutations and natural selection give some insects an advantage, and eventually gene
frequencies change until most have the trait.
b. Through the use of restriction enzymes and ligases, new sequences of DNA are
created and passed on to offspring.
c. The pesticides cause the synthesis of new proteins with altered amino acid sequences.
d. Insects learned to avoid the spray and their offspring also learn to avoid the spray.

Use the following information to answer the next question.

Gause’s Principle
Two similar species vying for a common resource cannot co-exist in a common area.
23. The reason why similar species cannot continue to co-exist according to Gause is due to:
a. Interspecific Competition
b. Intraspecific Competition
c. Law of the Minimum
d. Law of Tolerance

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 Use the following information to answer the next question

Lemmings are small, plant-eating rodents that live in underground burrows.

The data used to construct the graph below was collected during surveys of an area of 24
hectares.

Population Densities of Lemmings in Barrow,

Alaska, 1954-1974
250
Density (number per hectare)

200

150

100

50

0
1955 1960 1965 1970 1975
Year

24. Which row correctly identifies two density- dependent and two density- independent
factors that likely affected the size of the lemming population from 1954 to 1974?

Ro Density – Dependent Factors Density- Independent Factors

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 w

A ● Average Sumer Temperature ● Number of Predators

● Snow Depth ● Availability of Grass

B ● Number of Predators ● Average Sumer Temperature

● Availability of Grass ● Snow Depth

C ● Length of Days in Summer ● Availability of Grass

● Number of Predators in Winter ● Snow Depth

D ● Availability of Grass ● Length of Days in Summer

● Snow Depth ● Number of Predators in Winter

Numerical Response # 4

Use the following information to answer the next question

Examples of Ecological Relationships

1. Dwarf Mistletoe infects Lodgepole Pine and Jack Pine reducing its survival.

2. A female Oncideres Beetle lays her eggs under the bark on a branch of a Mimosa tree,
because the larval beetles cannot survive in a live branch, the female girdles (prunes)
the branch which soon dies and falls to the ground. The larvae grow in and feed on
the fallen branch and develop into adults. Without being pruned, the mimosa tree will
live for 25-30 years. However, if the Mimosa is pruned it has a life expectancy of
about 100 years.

3. Monarch Butterflies are bitter tasting to birds. Their coloration warns birds that
would otherwise eat them of their poison.

4. The Egret, a heron-like bird, follows grazing cattle and feeds on the insects disturbed
as the cattle move through the grass.

Match the ecological relationships, as numbered above, with the types of relationships listed
below.

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Ecological 4 1 3 2
Relationship

Type of Predation Parasitism Commensalism Mutualism

Relationship

(Record your 4 digit response in the NR section of your answer card.)

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 Written Response Section- V1a
Name:

Class: Biology 30 -

Question # 1
List 3 conditions required for the Hardy – Weinberg Principle to hold true:
Large populations

No migration

No Natural selection

Use the following information to answer the next 2 questions

The Trumpeter Swan is a large bird with a wingspan of 2.0-2.5 m. They mate for life and both
parents participate in raising the young cygnets (baby swans). The average lifespan of a swan is
24 years. In the early 19th and 20th Centuries Trumpeter Swans were heavily hunted and very
vulnerable to lead poisoning which resulted in their almost near extinction by the early 20 th
Century. However the few remaining swans mated to rebuild the population numbers up to an
acceptable level to remove it from the endangered species list, however the genetic diversity in
the gene pool remains low.
Question # 2
a) Identify the Reproductive Strategy of the Inbreeding
Trumpeter Swan

b) List one characteristic from this article small populations often inbreed to increase in
that supports your answer above. numbers and this results in less genetic
diversity as described by this article in having
“the genetic diversity in the gene pool
remains low”.

Question # 3

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 a) Would the swan’s population story be a classic example of the founder effect or the
bottleneck effect? ___Bottleneck affect_______________________________________
b) Provide a reason for choosing your answer above:

The population was drastically reduced, and their population now has a smaller gene pool
because of this drastic reduction and only those who survived pass on their characteristics/genes
they have.

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