Ecology Ecosystem Energy Flow Questions and Answers

Question 1

Which of the following best describes the relationship between Gross Primary Production (GPP) and Net Primary Production (NPP)?

Accepted Answer

NPP is the energy remaining from GPP after producers have accounted for their own metabolic needs through respiration.

Answer

NPP is the total energy captured by producers, while GPP is the energy available to consumers.

Answer

GPP and NPP are identical measures of the total solar energy converted to biomass.

Answer

GPP is the rate of biomass accumulation by consumers, whereas NPP is the rate for producers.

Question 2

In a terrestrial food web, a rabbit eats grass, and a fox eats the rabbit. In this chain, the rabbit functions as which of the following?

Accepted Answer

A primary consumer

Answer

A secondary consumer

Answer

A producer

Answer

A decomposer

Question 3

The '10% Rule' of energy transfer between trophic levels explains why which of the following is true?

Accepted Answer

Food chains are generally limited to four or five trophic levels.

Answer

The biomass of producers is typically much smaller than the biomass of top carnivores.

Answer

Ecosystems can support an infinite number of trophic levels.

Answer

Energy is recycled efficiently, with 10% being permanently destroyed at each level.

Question 4

If the producer level in a grassland ecosystem contains 25,000 kcal/m²/year of energy, approximately how much energy would be expected to be available to the tertiary consumers?

Accepted Answer

25 kcal/m²/year

Answer

2,500 kcal/m²/year

Answer

250 kcal/m²/year

Answer

2.5 kcal/m²/year

Question 5

Which group of organisms is essential for returning nutrients from dead organic matter back into the soil, making them available for producers?

Accepted Answer

Decomposers

Answer

Tertiary consumers

Answer

Primary consumers

Answer

Autotrophs

Question 6

What is the ultimate source of energy for the vast majority of ecosystems on Earth?

Accepted Answer

Solar radiation

Answer

Geothermal heat from the Earth's core

Answer

Chemical energy from inorganic compounds

Answer

Kinetic energy from wind and tides