Question

1. the energy available at each trophic level is usually about what percent of the level below it?

a) 100%
b) 50%
c) 25%
d) 10%

1. which type of pyramid shows the number of organisms at each trophic level?

a) energy pyramid
b) pyramid of numbers
c) biomass pyramid
d) pyramid of energy

1. what happens to most of the energy as it moves up the trophic levels in a food chain?

a) it increases
b) it is stored as fat
c) it is lost as heat
d) it is turned into water

1. which trophic level has the smallest amount of energy available?

a) producers
b) primary consumers
c) secondary consumers
d) tertiary consumers
open - ended questions: answer the following questions in complete sentences.

1. explain why there are usually fewer organisms at the top of an ecological pyramid than at the bottom.
2. describe what would happen to an ecosystem if the producer level suddenly decreased.
3. give an example of an ecosystem and briefly describe what its pyramid of numbers might look like.

Explanation:

1. In an ecosystem, the energy available at each trophic level is about 10% of the level below it due to energy loss at each transfer, known as the 10 - percent rule.
2. The pyramid of numbers shows the number of organisms at each trophic level. It represents the count of individual organisms in each level of the food chain.
3. As energy moves up the trophic levels in a food chain, most of it is lost as heat during metabolic processes like respiration.
4. Tertiary consumers are at the top of the food chain. Since energy is lost at each trophic - level transfer, they have the smallest amount of energy available.

Answer:

1. D. 10%
2. B. Pyramid of numbers
3. C. It is lost as heat
4. D. Tertiary consumers