Question 1

Which of the following best describes the difference between energy flow and nutrient cycling in an ecosystem?

Accepted Answer

Energy flows in one direction and exits as heat, while nutrients cycle within the ecosystem.

Question 2

Gross Primary Production (GPP) is defined as:

Accepted Answer

The total energy produced by autotrophs through photosynthesis.

Question 3

Which ecosystem has the highest net primary productivity according to the provided chart?

Accepted Answer

Algal beds and reefs

Question 4

In terrestrial ecosystems, what factors most strongly influence net primary productivity?

Accepted Answer

Temperature and rainfall

Question 5

Which of the following is a major reservoir for carbon in the carbon cycle?

Accepted Answer

Sedimentary rock

Question 6

What process removes CO$$_2$$ from the atmosphere in the carbon cycle?

Accepted Answer

Photosynthesis

Question 7

Which of the following is NOT a way humans alter nutrient cycles?

Accepted Answer

Evaporation of water from oceans

Question 8

Residence time in a biogeochemical cycle refers to:

Accepted Answer

The time a nutrient spends in a particular reservoir before moving to another.

Question 9

Which process in the water cycle is responsible for moving water from plants to the atmosphere?

Accepted Answer

Transpiration

Question 10

In the nitrogen cycle, which process converts atmospheric N$$_2$$ into a form usable by plants?

Accepted Answer

Nitrogen fixation

Question 11

A farmer applies excess nitrogen fertilizer to a field. Which environmental consequence is most likely?

Accepted Answer

Eutrophication of nearby aquatic ecosystems

Question 12

Which equation best represents the relationship between Gross Primary Production (GPP), Net Primary Production (NPP), and plant respiration (R)?

Accepted Answer

$$\mathrm{GPP} = \mathrm{NPP} + R$$

Question 13

Which of the following best explains why energy cannot cycle within an ecosystem?

Accepted Answer

Energy is lost as heat at each trophic level, preventing its recycling.

Question 14

Which of the following is a correct statement about the phosphorus cycle?

Accepted Answer

Phosphorus is mainly stored in sedimentary rock and soil.

Question 15

If a lake receives runoff containing phosphorus from agricultural fields, what is the most likely ecological effect?

Accepted Answer

Eutrophication leading to algal blooms

Question 16

Which of the following is an example of a detritivore in an ecosystem?

Accepted Answer

Earthworm

Question 17

Which process in the carbon cycle is directly responsible for returning CO$$_2 to $$the atmosphere from living organisms?

Accepted Answer

Cellular respiration

Question 18

A scientist measures the amount of energy stored in plant tissue in a forest. What is she measuring?

Accepted Answer

Net Primary Production

Question 19

Which of the following best describes the fate of energy input from sunlight in an ecosystem?

Accepted Answer

It flows through trophic levels and is eventually lost as heat.

Question 20

Which of the following is a real-world example of human alteration of the water cycle?

Accepted Answer

Diverting river water for irrigation

Ecosystem Ecology: Energy Flow and Biogeochemical Cycles

Study Guide - Practice Questions