Population ecology - growth models, carrying capacity, population interactions - Question Bank

1. If a population's size is above the carrying capacity (K), what is expected to happen to the growth rate?
A) It will be positive and increasing.
B) It will be positive but decreasing.
C) It will be negative.
D) It will be zero.
2. Which type of population interaction is represented by the symbol -/-?
A) Mutualism (+/+)
B) Commensalism (+/0)
C) Predation (+/-)
D) Competition (-/-)
3. A population experiencing a negative growth rate (dN/dt < 0) implies:
A) Birth rate exceeds death rate.
B) Death rate exceeds birth rate.
C) Birth rate equals death rate.
D) The population is at carrying capacity.
4. The study of how populations interact with each other and their environment is known as:
A) Population genetics
B) Population dynamics
C) Population ecology
D) Population distribution
5. When resources are abundant, a population is most likely to exhibit which growth pattern?
A) Logistic growth
B) Stable growth
C) Exponential growth
D) Declining growth
6. The concept of 'niche' in ecology refers to:
A) The physical space an organism occupies.
B) The role an organism plays in its ecosystem, including its interactions and resource use.
C) The reproductive rate of a species.
D) The population density of a species.
7. Which of the following is an example of a density-dependent limiting factor that affects human populations?
A) Natural disasters
B) Pandemics
C) Climate change
D) Volcanic eruptions
8. In the Lotka-Volterra predator-prey model, oscillations in population sizes are caused by:
A) Direct competition between predators.
B) The time lag between predator and prey population changes.
C) Unlimited prey availability.
D) Constant predator mortality.
9. The logistic growth model predicts that a population's growth rate will slow down as it approaches:
A) Zero population size
B) Its intrinsic rate of increase
C) The carrying capacity
D) Maximum density
10. A group of individuals of the same species living in the same area at the same time, capable of interbreeding, is defined as a:
A) Community
B) Ecosystem
C) Population
D) Species
11. The term 'population interaction' refers to:
A) The genetic makeup of a population.
B) The spatial distribution of individuals within a population.
C) The relationships between different species or individuals within a population.
D) The rate at which a population changes over time.
12. A population's intrinsic rate of increase (r) is highest when:
A) Birth rates are low and death rates are high.
B) Birth rates are high and death rates are low.
C) Birth rates equal death rates.
D) The population is at carrying capacity.
13. Which of the following interactions is characterized by + / - relationship?
A) Mutualism
B) Commensalism
C) Predation
D) Competition
14. What is the term for a population's tendency to increase in size when it is small and decrease when it is large, often leading to extinction?
A) Carrying capacity effect
B) Density-dependent limitation
C) The Allee effect
D) Resource competition
15. In the logistic growth model, if N approaches 0, the growth rate (dN/dt) is approximately:
A) rK
B) 0
C) rN
D) -rK
16. Which of the following is an example of a density-dependent factor that can regulate population size?
A) Volcanic eruption
B) Availability of nesting sites
C) Hurricane
D) Drought
17. Niche partitioning is a mechanism that allows:
A) Species to coexist by specializing on different resources or parts of resources.
B) One species to outcompete another.
C) Populations to grow exponentially.
D) Predators to eliminate prey populations.
18. If two species compete for the same niche, one species is likely to be eliminated or driven to extinction, according to the:
A) Principle of limiting factors
B) Competitive exclusion principle
C) Theory of island biogeography
D) Island model of colonization
19. The principle that states that two species competing for the same limiting resources cannot coexist indefinitely is known as:
A) The Allee effect
B) The competitive exclusion principle
C) The Lotka-Volterra principle
D) The Gause hypothesis
20. What happens to the predator population when the prey population declines significantly?
A) It increases due to abundant food.
B) It remains stable.
C) It declines due to lack of food.
D) It has no effect on the predator population.
21. In a predator-prey cycle, an increase in the prey population typically leads to:
A) A decrease in the predator population.
B) A decrease in the prey population.
C) An increase in the predator population.
D) No change in the predator population.
22. A population's growth is limited by the availability of food, water, shelter, and mates. These are collectively known as:
A) Biotic potential
B) Carrying capacity
C) Environmental resistance
D) Population density
23. Which scenario best describes intraspecific competition?
A) Lions competing with hyenas for antelope.
B) Deer competing with rabbits for grass.
C) Two male deer fighting for mating rights.
D) A hawk preying on a mouse.
24. The equation for logistic growth is often written as dN/dt = rN(K-N)/K. What does dN/dt represent?
A) The population size at time t
B) The rate of change of population size over time
C) The intrinsic rate of increase
D) The carrying capacity
25. A population's biotic potential is:
A) The maximum growth rate under ideal conditions.
B) The carrying capacity of the environment.
C) The rate of mortality.
D) The impact of density-dependent factors.
26. Allelopathy, where one plant produces chemicals that inhibit the growth of another, is a form of:
A) Mutualism
B) Commensalism
C) Amensalism
D) Predation
27. Which interaction benefits both species involved?
A) Parasitism
B) Predation
C) Mutualism
D) Amensalism
28. When a population fluctuates around the carrying capacity, it suggests:
A) Exponential growth is occurring.
B) The environment is stable and K is constant.
C) The population is limited by density-independent factors.
D) The population has exceeded K and is declining rapidly.
29. In the logistic growth model, when the population size (N) is much smaller than the carrying capacity (K), the growth rate is:
A) Close to zero
B) Negative
C) Close to the exponential growth rate (rN)
D) At its maximum negative value
30. The relationship between a lion and a zebra is an example of:
A) Parasitism
B) Mutualism
C) Predation
D) Commensalism
31. When two bird species nest in the same tree and compete for nesting sites, this is an example of:
A) Predation
B) Mutualism
C) Commensalism
D) Interspecific competition
32. Barnacles attached to a whale, benefiting from a place to live and feed while the whale is largely unaffected, is an example of:
A) Parasitism
B) Mutualism
C) Commensalism
D) Competition
33. The interaction between a tick and a dog is an example of:
A) Mutualism
B) Commensalism
C) Parasitism
D) Predation
34. If a population is experiencing exponential growth, what does this imply about the environment?
A) Resources are limited.
B) Environmental resistance is high.
C) Conditions are favorable with ample resources.
D) The population is at carrying capacity.
35. Which of the following is an example of a density-independent factor affecting a population?
A) Disease outbreak
B) Competition for food
C) A severe frost
D) Predator-prey dynamics
36. What is the term for the maximum number of individuals of a species that an environment can sustainably support?
A) Population density
B) Biotic potential
C) Carrying capacity
D) Intrinsic rate of increase
37. In the logistic growth equation dN/dt = rN(1 - N/K), the term (1 - N/K) represents:
A) The potential for growth
B) The effect of environmental resistance
C) The population's intrinsic rate of increase
D) The carrying capacity
38. The formula for the exponential growth rate is dN/dt = rN, where 'r' represents:
A) Carrying capacity
B) Environmental resistance
C) The intrinsic rate of natural increase
D) Population density
39. Amensalism is an interaction where:
A) Both species benefit.
B) One species benefits, and the other is harmed.
C) One species is harmed, and the other is unaffected.
D) Both species are harmed.
40. Commensalism is an interaction where:
A) Both species benefit.
B) One species benefits, and the other is harmed.
C) One species benefits, and the other is unaffected.
D) Both species are harmed.
41. Parasitism is characterized by:
A) Both host and parasite benefit.
B) The parasite benefits, and the host is harmed.
C) The host benefits, and the parasite is harmed.
D) Neither the host nor the parasite is significantly affected.
42. Competition occurs when:
A) Two species have a predator-prey relationship.
B) Two or more organisms require the same limited resource.
C) One species benefits at the expense of another.
D) Both species involved in the interaction benefit.
43. Predation is an interaction where:
A) One organism hunts and kills another for food.
B) Two species live in close association.
C) One organism lives on or inside another, causing harm.
D) Two species compete for the same limited resources.
44. Mutualism is a type of population interaction where:
A) One species benefits, and the other is harmed.
B) Both species benefit.
C) One species benefits, and the other is unaffected.
D) Both species are harmed.
45. Factors like floods, wildfires, and extreme temperatures that limit population growth regardless of population density are called:
A) Density-dependent factors
B) Biotic potential
C) Environmental resistance
D) Density-independent factors
46. Which of the following is a density-dependent factor that limits population growth?
A) Drought
B) Wildfire
C) Predation
D) Extreme temperature
47. When a population reaches its carrying capacity (K), its growth rate approaches:
A) Maximum positive rate
B) Zero
C) Maximum negative rate
D) An oscillating rate
48. The logistic growth model, often depicted as an 'S-shaped' curve, accounts for:
A) Unlimited resources
B) Environmental resistance
C) Constant birth rates
D) Unrestricted migration
49. In the logistic growth model, what does 'K' represent?
A) The intrinsic rate of increase
B) The carrying capacity of the environment
C) The initial population size
D) The time taken to reach carrying capacity
50. The 'J-shaped' growth curve is characteristic of which population growth model?
A) Logistic growth
B) Exponential growth
C) Carrying capacity limited growth
D) Density-dependent growth