Biology Unit 4 Review / Retake.

Q1. What is population density?

A) The total number of individuals in a population.

B) The study of population statistics and trends.

C) The average number of individuals living per unit of area or volume.

D) The way individuals are spaced out across a specific habitat.

The answer is C.

C) The average number of individuals living per unit of area or volume.

Population density is a measurement that quantifies how many individuals exist within a specified area, providing insight into space utilization and resource availability.

Therefore A, B, and D are incorrect.

Q2. Defining the Immigration VS Emigration.

A) Immigration is moving into an area; emigration is moving out of an area.

B) Immigration is moving out of an area; emigration is moving into an area.

C) Both immigration and emigration mean moving within the same area.

D) Immigration refers only to animals; emigration refers only to humans.

The answer is A

A) Immigration is moving into an area; emigration is moving out of an area.

Therefore B, C, and D are incorrect.

Q3. Birth rate vs. Death rate.

A) The birth rate describes immigration levels, while the death rate describes emigration levels.

B) The birth rate is the number of individuals born per unit of time, and the death rate is the number of individuals that die per unit of time.

C) The birth rate calculates the average lifespan of a species, while the death rate calculates how many offspring a species can produce.

D) The birth rate is always higher than the death rate in a stable population.

The answer is B

B) The birth rate is the number of individuals born per unit of time, and the death rate is the number of individuals that die per unit of time.

Options A, C, and D are NOT correct.

Q4. Examples of survivorship curves.

A) Type I (late loss), Type II (constant loss), and Type III (early loss).

B) Linear, Exponential, and Logistic curves.

C) J-shaped and S-shaped curves.

D) Density-dependent and density-independent curves.

The answer is A

A) Type I (late loss), Type II (constant loss), and Type III (early loss).

Options B, C and D are NOT correct.

Q5. What is ecological succession?

A) The process by which a population reaches its maximum carrying capacity in an ecosystem.

B) The steady, predictable change in an ecosystem over time, often following a disturbance.

C) The process of an individual organism adapting to a new environment during its lifetime.

D) The introduction of a new, invasive species into an existing habitat.

The answer is B

B) The steady, predictable change in an ecosystem over time, often following a disturbance.

Q6. Example of pioneer species.

A) Large, slow-growing trees like oak and maple.

B) Animals that migrate long distances, such as wildebeest.

C) Lichens and mosses that grow on bare rock.

D) Large predators at the top of the food chain, such as wolves or killer whales.

The answer is C

C) Lichens and mosses that grow on bare rock.

Options A, B, and D are incorrect.

Q7. A keystone species is one in an ecosystem that...

A) Has the largest population size of all species present.

B) Is at the very bottom of the food web.

C) Has a disproportionately large impact on its environment relative to its abundance, maintaining ecosystem structure.

D) Migrates annually between two different ecosystems.

The answer is C

C) Has a disproportionately large impact on its environment relative to its abundance, maintaining ecosystem structure.

Options A, B, and D are incorrect.

Q8. Mother Nature uses biodiversity to increase ecosystem resilience.

A) True

B) False

That is TRUE.

Mother Nature USES biodiversity to increase ecosystem resilience.

It’ can’t be false.

Q9. Population control is often achieved through…

A) Unlimited resource availability leading to exponential growth.

B) Density-independent factors like constant sunshine and perfect temperature.

C) Limiting factors and environmental resistance (e.g., disease, competition, limited food/water).

D) Purely human intervention methods like hunting or conservation laws.

The answer is C.

C) Limiting factors and environmental resistance (e.g., disease, competition, limited food/water).

Options A, B, and D are incorrect.

Q10. The physical arrangement of living organisms in a given area is called population ____________.

A) Density

B) Size

C) Dispersion (or Distribution)

D) Carrying Capacity

The answer is C

C) Dispersion (or Distribution)

Options A, B, and D are NOT correct.

Q11. What is NOT an example of an area that is likely to undergo primary succession?

A) A newly formed volcanic island.

B) A bare rock surface after a glacier retreats.

C) A parking lot paved over by humans.

D) An abandoned farm field after a harvest.

The answer is D

D) An abandoned farm field after a harvest.

INCORRECT OPTIONS: A, B, and C.

Q12. ___ are the first organisms (lichens and mosses) to colonize an area and begin the process of soil formation.

A) Climax species

B) Keystone species

C) Apex predators

D) Pioneer species

The answer is D

D) Pioneer species

Climax species, Keystone species, Apex predators are NOT the first organisms (lichens and mosses) to colonize an area and begin the process of soil formation.

Q13. Survivorship curves can tell us something about longevity, reproductive rates and parental care in all living things.

A) True

B) False

That is TRUE.

Survivorship curves can tell us something about longevity, reproductive rates and parental care in all living things.

Although, it can’t be false.

Q14. Carrying Capacity is the stabilization of the population curve due to environmental resistance and limiting factors.

A) True

B) False

That is True.

Carrying Capacity is the stabilization of the population curve due to environmental resistance and limiting factors.

It can’t be false.