Question

In an aquatic ecosystem, the trophic level equivalent to cows in grasslands is :

• A. Nekton
• B. Phytoplankton
• C. Benthos
• D. Zooplankton

Answer 1

The correct option is D Zooplankton

Zooplanktons are the microscopic animals that on the phytoplanktons in an aquatic ecosystem. These are truly herbivorous and form the second trophic level (primary consumers) equivalent to cows in grasslands.

In a grassland, herbivores like cow are the consumers that eat primary producers, i.e., grass. In a pond or lake, consumers comprise of zooplanktons that feed on phytoplanktons.

Nekton (or swimmers) are heterotrophic living organisms that are able to swim and move independently of currents. Benthos is used to refer to organisms at the bottom of freshwater bodies of water, such as lakes, rivers, and streams. Clams, worms, oysters, shrimp-like crustaceans and mussels are all examples of benthic organisms.

Phytoplankton are tiny forms of plant life on the sea. They are single-celled plants and use the energy of the sun to assimilate carbon supplying oxygen and synthesise compounds.

Thus, the correct answer is option B.