BIOD 102 MODULE 3 EXAM 2026/2027 | Essential Biology II
with Lab | Verified Q&A | Grade A | Portage Learning | Pass
Guaranteed - A+ Graded
SECTION 1: POPULATION ECOLOGY (15 Questions)
Q1: Which of the following best describes a population in ecological terms?
A. All the organisms living in a particular ecosystem
B. All the individuals of a single species living in a defined area at a given time
[CORRECT]
C. All the species interacting within a biological community
D. The total biomass of all organisms in a habitat
Correct Answer: B
Rationale: A population consists of all individuals of the same species inhabiting a
specific geographic area simultaneously. Option A describes a community, C describes
a biological community, and D refers to biomass rather than population definition.
Q2: In a mark-recapture study, 200 rabbits were initially captured, marked, and released.
In a second capture of 150 rabbits, 30 were marked. What is the estimated population
size?
A. 750
B. 900
C. 1,000 [CORRECT]
D. 1,200
Correct Answer: C
Rationale: Using the Lincoln-Petersen index formula N = (M × C) / R, where M = 200
marked, C = 150 captured, and R = 30 recaptured: N = (200 × 150) / 30 = 1,000. This
method assumes random mixing and no significant immigration, emigration, births, or
deaths between sampling events.
Q3: A population of deer exhibits a clumped dispersion pattern. What is the most likely
ecological explanation for this distribution?
,A. Uniform resource distribution across the habitat
B. Strong territorial behavior among individuals
C. Patchy resource availability and social behavior [CORRECT]
D. Random environmental factors affecting individual placement
Correct Answer: C
Rationale: Clumped dispersion results from uneven resource distribution and/or social
groupings, which is the most common pattern in nature. Uniform dispersion (B) results
from territoriality, while random dispersion (D) occurs when environmental conditions
are consistent and individuals do not interact strongly.
Q4: Which survivorship curve characterizes organisms that produce many offspring with
high juvenile mortality, such as oysters or insects?
A. Type I
B. Type II
C. Type III [CORRECT]
D. Type IV
Correct Answer: C
Rationale: Type III survivorship shows high mortality early in life with few individuals
surviving to old age, typical of r-selected species with minimal parental investment.
Type I (A) shows low early mortality (humans, elephants), while Type II (B) shows
constant mortality throughout life.
Q5: In the logistic growth model, what happens to population growth rate as the
population size (N) approaches carrying capacity (K)?
A. Growth rate increases exponentially
B. Growth rate remains constant
C. Growth rate approaches zero [CORRECT]
D. Growth rate becomes negative immediately
Correct Answer: C
Rationale: The logistic equation dN/dt = rN[(K-N)/K] shows that as N approaches K, the
term (K-N)/K approaches zero, slowing population growth. Growth only becomes
negative if N exceeds K due to overshoot, not simply as N approaches K.
Q6: Which of the following is a density-dependent factor regulating population size?
A. Severe drought affecting all individuals equally
, B. A volcanic eruption destroying habitat
C. Increased competition for food as population density rises [CORRECT]
D. Random lightning strikes causing mortality
Correct Answer: C
Rationale: Density-dependent factors intensify with increasing population density,
including competition, predation, and disease. Options A, B, and D are
density-independent factors that affect populations regardless of their size.
Q7: A species that matures early, produces many small offspring, and provides minimal
parental care is classified as:
A. K-selected
B. r-selected [CORRECT]
C. Type I strategist
D. Equilibrium species
Correct Answer: B
Rationale: r-selected species maximize reproductive rate (r) in unpredictable
environments, producing numerous offspring with low survival probability. K-selected
species (A) mature late, produce few offspring, and invest heavily in parental care,
thriving near carrying capacity.
Q8: Which demographic factor would directly increase a population's growth rate?
A. Increased emigration
B. Decreased birth rate
C. Increased immigration [CORRECT]
D. Increased death rate
Correct Answer: C
Rationale: Population growth rate is calculated as (births + immigration) - (deaths +
emigration). Immigration adds individuals to the population, while emigration (A),
decreased birth rate (B), and increased death rate (D) would decrease population
growth.
Q9: In human population demographics, the age structure diagram with a broad base
and narrow top indicates:
A. A stable population with balanced birth and death rates
B. A declining population with low birth rates
with Lab | Verified Q&A | Grade A | Portage Learning | Pass
Guaranteed - A+ Graded
SECTION 1: POPULATION ECOLOGY (15 Questions)
Q1: Which of the following best describes a population in ecological terms?
A. All the organisms living in a particular ecosystem
B. All the individuals of a single species living in a defined area at a given time
[CORRECT]
C. All the species interacting within a biological community
D. The total biomass of all organisms in a habitat
Correct Answer: B
Rationale: A population consists of all individuals of the same species inhabiting a
specific geographic area simultaneously. Option A describes a community, C describes
a biological community, and D refers to biomass rather than population definition.
Q2: In a mark-recapture study, 200 rabbits were initially captured, marked, and released.
In a second capture of 150 rabbits, 30 were marked. What is the estimated population
size?
A. 750
B. 900
C. 1,000 [CORRECT]
D. 1,200
Correct Answer: C
Rationale: Using the Lincoln-Petersen index formula N = (M × C) / R, where M = 200
marked, C = 150 captured, and R = 30 recaptured: N = (200 × 150) / 30 = 1,000. This
method assumes random mixing and no significant immigration, emigration, births, or
deaths between sampling events.
Q3: A population of deer exhibits a clumped dispersion pattern. What is the most likely
ecological explanation for this distribution?
,A. Uniform resource distribution across the habitat
B. Strong territorial behavior among individuals
C. Patchy resource availability and social behavior [CORRECT]
D. Random environmental factors affecting individual placement
Correct Answer: C
Rationale: Clumped dispersion results from uneven resource distribution and/or social
groupings, which is the most common pattern in nature. Uniform dispersion (B) results
from territoriality, while random dispersion (D) occurs when environmental conditions
are consistent and individuals do not interact strongly.
Q4: Which survivorship curve characterizes organisms that produce many offspring with
high juvenile mortality, such as oysters or insects?
A. Type I
B. Type II
C. Type III [CORRECT]
D. Type IV
Correct Answer: C
Rationale: Type III survivorship shows high mortality early in life with few individuals
surviving to old age, typical of r-selected species with minimal parental investment.
Type I (A) shows low early mortality (humans, elephants), while Type II (B) shows
constant mortality throughout life.
Q5: In the logistic growth model, what happens to population growth rate as the
population size (N) approaches carrying capacity (K)?
A. Growth rate increases exponentially
B. Growth rate remains constant
C. Growth rate approaches zero [CORRECT]
D. Growth rate becomes negative immediately
Correct Answer: C
Rationale: The logistic equation dN/dt = rN[(K-N)/K] shows that as N approaches K, the
term (K-N)/K approaches zero, slowing population growth. Growth only becomes
negative if N exceeds K due to overshoot, not simply as N approaches K.
Q6: Which of the following is a density-dependent factor regulating population size?
A. Severe drought affecting all individuals equally
, B. A volcanic eruption destroying habitat
C. Increased competition for food as population density rises [CORRECT]
D. Random lightning strikes causing mortality
Correct Answer: C
Rationale: Density-dependent factors intensify with increasing population density,
including competition, predation, and disease. Options A, B, and D are
density-independent factors that affect populations regardless of their size.
Q7: A species that matures early, produces many small offspring, and provides minimal
parental care is classified as:
A. K-selected
B. r-selected [CORRECT]
C. Type I strategist
D. Equilibrium species
Correct Answer: B
Rationale: r-selected species maximize reproductive rate (r) in unpredictable
environments, producing numerous offspring with low survival probability. K-selected
species (A) mature late, produce few offspring, and invest heavily in parental care,
thriving near carrying capacity.
Q8: Which demographic factor would directly increase a population's growth rate?
A. Increased emigration
B. Decreased birth rate
C. Increased immigration [CORRECT]
D. Increased death rate
Correct Answer: C
Rationale: Population growth rate is calculated as (births + immigration) - (deaths +
emigration). Immigration adds individuals to the population, while emigration (A),
decreased birth rate (B), and increased death rate (D) would decrease population
growth.
Q9: In human population demographics, the age structure diagram with a broad base
and narrow top indicates:
A. A stable population with balanced birth and death rates
B. A declining population with low birth rates
