Q: A population of rabbits in a field has a current size ($$N) of 500$$, an intrinsic rate of increase ($$r) of 0.2 $$per year, and a carrying capacity ($$K) of 1000. $$Using the logistic growth equation $$\displaystyle \Delta N = rN \left(1 - \frac{N}{K}\right)$$, what is the expected change in population size ($$\Delta N) $$for the next year?

$$\Delta N = 0.2 \times 500 \times \left(1 - \frac{500}{1000}\right) = 50$$

Question 1

Which of the following best describes the difference between exponential and logistic population growth models?

Accepted Answer

Exponential growth assumes unlimited resources, while logistic growth incorporates carrying capacity ($$K) as a $$limiting factor.

Question 2

A population of rabbits in a field has a current size ($$N) of 500$$, an intrinsic rate of increase ($$r) of 0.2 $$per year, and a carrying capacity ($$K) of 1000. $$Using the logistic growth equation $$\displaystyle \Delta N = rN \left(1 - \frac{N}{K}\right)$$, what is the expected change in population size ($$\Delta N) $$for the next year?

Accepted Answer

$$\Delta N = 0.2 	imes 500 	imes \left(1 - \frac{500}{1000}ight) = 50$$

Question 3

Which of the following is an example of a density-dependent factor regulating population growth?

Accepted Answer

A contagious disease spreading more rapidly as population density increases.

Question 4

Which survivorship curve is most likely to be associated with a species that produces many small offspring with little parental care, such as oysters?

Accepted Answer

Type III

Question 5

In Gause’s classic experiments with Paramecium, what principle was demonstrated when two species with identical niches were grown together?

Accepted Answer

Competitive exclusion principle

Question 6

Which of the following best illustrates Batesian mimicry?

Accepted Answer

A harmless king snake resembling a venomous coral snake.

Question 7

Which of the following is a key difference between a food chain and a food web?

Accepted Answer

A food web shows multiple interconnected food chains, while a food chain shows a single linear pathway of energy flow.

Question 8

Which of the following best describes the role of keystone species in a community?

Accepted Answer

They have a disproportionately large effect on community structure relative to their abundance.

Question 9

Which process in the nitrogen cycle is responsible for converting atmospheric nitrogen ($$N_2) $$into a form usable by plants?

Accepted Answer

Nitrogen fixation

Question 10

Why does energy flow through ecosystems rather than cycle, according to the second law of thermodynamics?

Accepted Answer

Because some energy is lost as heat at each trophic transfer, making it unavailable for reuse.

Question 11

Which of the following is a real-world example of biological magnification?

Accepted Answer

PCBs accumulating at higher concentrations in fish-eating birds in the Great Lakes.

Question 12

Which of the following best explains why worldwide agriculture could feed more people if all humans consumed only plant material?

Accepted Answer

Energy transfer between trophic levels is inefficient, with only about 10% of energy passed to the next level.

Question 13

Which of the following is an example of an ecosystem engineer?

Accepted Answer

Beavers building dams that alter water flow and create wetlands.

Question 14

Which of the following best describes the intermediate disturbance hypothesis?

Accepted Answer

Moderate levels of disturbance foster greater species diversity than low or high levels of disturbance.

Question 15

Which of the following is a primary cause of the latitudinal gradient in species richness?

Accepted Answer

Greater evolutionary history and higher productivity in the tropics.

Question 16

Which of the following is a key difference between primary and secondary succession?

Accepted Answer

Primary succession occurs on newly formed or exposed surfaces without soil, while secondary succession occurs where soil remains after a disturbance.

Question 17

Which of the following best describes the greenhouse effect?

Accepted Answer

The trapping of heat by greenhouse gases in the atmosphere, warming the Earth's surface.

Question 18

Which of the following is a correct statement about metapopulations?

Accepted Answer

They are groups of local populations linked by immigration and emigration.

Question 19

Which of the following is an example of bioremediation in restoration ecology?

Accepted Answer

Using bacteria to detoxify oil spills in marine environments.

Question 20

Which of the following best explains why effective population size ($$N_e) is $$often smaller than the total population size ($$N$$)?

Accepted Answer

Not all individuals contribute equally to the next generation due to factors like unequal sex ratios and variation in reproductive success.

Ecology, Ecosystems, and Conservation Biology: Study Notes for BIOL 107 Exam 1

Study Guide - Practice Questions

Study Guide - Flashcards