Question

Which one of the following types of organisms occupies more than one trophic level in a pond ecosystem?

• A. Phytoplankton
• B. Frog
• C. Zooplankton
• D. Fish

Answer 1

The correct option is D

Fish

The correct option is D.

Explanation for the correct option:

1. Fish in ponds live on several trophic levels.
2. Small fish are a secondary source of food.
3. They eat the main consumer.
4. Big fish serve as the tertiary consumer.

Explanation for the incorrect options:

Option A:

1. The base of the aquatic food web is composed of primary producers, which include bacteria, phytoplankton, and algae.
2. Primary producers don't require food because they can create their own energy.

Option B:

1. Since they consume and feed on producers, these creatures fall under the heterotroph category since they are unable to make or manufacture their own food.
2. Frogs are heterotrophs as a result. Frogs are secondary consumers in the environment, eating the prime consumers.

Option C:

The zooplankton population is made up of main consumers, which eat floating algae, and secondary consumers, who eat other zooplankton.

Final answer: Organisms occupying more than one trophic level in a pond ecosystem are Fish.