Phytoplankton are microscopic photosynthesizing organisms that typically live in the upper layers of the ocean. what trophic level do phytoplankton belong to? primary producers
decomposers
primary consumers
secondary producers

Primary producers

Phytoplankton are microscopic marine organisms. These are considered under plants, as they are capable of synthesizing their own food by the process of photosynthesis. Examples includes cynobacteria, dinoflagellates and diatoms. These are abundantly present in marine ecosystem. They are consumed by many marine animals such as fishes and marine mammals.Therefore, they are included in the primary producer trophic level in an ocean ecosystem.

an active site is a region that is present on an enzyme where the reactants or the substrate molecules we can say bind and experience a chemical reaction. the substrate is basically a reactant whose concentration is changing and that is converting into a product after binding at the active site of an enzyme