Question

1. what essential ecosystem service is provided by biodiversity that directly supports human survival?

a. soil erosion
b. clean water and pollution
c. air pollution control
d. urban development

1. what role do decomposers play in an ecosystem?

a. they are primary producers.
b. they are top predators.
c. they feed on primary consumers.
d. they break down dead organic matter.

1. the influx of individuals into a population from outside sources is known as:

a. displacement
b. immigration
c. migration
d. emigration

Explanation:

• For question 7, biodiversity helps in water purification and pollination which are crucial for human survival. Soil erosion is a negative process, air - pollution control is part of the broader ecosystem service but not as directly linked as clean water and pollination, and urban development is not an ecosystem service provided by biodiversity.
• For question 8, decomposers break down dead organic matter, recycling nutrients back into the ecosystem. They are not primary producers (which are plants), not top predators, and do not feed on primary consumers directly.
• For question 9, immigration is the movement of individuals into a population from outside sources. Displacement is a more general term not specific to population influx, migration is a broader term that can include both in - and out - movement, and emigration is the movement out of a population.

Answer:

1. b. Clean water and pollination
2. d. They break down dead organic matter
3. b. Immigration