Which term describes microscopic floating organisms that form the base of many ocean food chains?

Which term describes microscopic floating organisms that form the base of many ocean food chains?

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

Answer: (A)

Phytoplankton. These are the microscopic, floating organisms that perform photosynthesis, turning sunlight into chemical energy and forming the energy foundation for many ocean food webs. While plankton is the broad umbrella term for all drifting organisms (including both phytoplankton and zooplankton), the base of the food chain specifically refers to the photosynthetic, primary-producing group—phytoplankton. Zooplankton are tiny animals that eat phytoplankton, and benthos are bottom-dwelling organisms, not floating near the surface.

Phytoplankton. These are the microscopic, floating organisms that perform photosynthesis, turning sunlight into chemical energy and forming the energy foundation for many ocean food webs. While plankton is the broad umbrella term for all drifting organisms (including both phytoplankton and zooplankton), the base of the food chain specifically refers to the photosynthetic, primary-producing group—phytoplankton. Zooplankton are tiny animals that eat phytoplankton, and benthos are bottom-dwelling organisms, not floating near the surface.