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Which organisms make up plankton in freshwater lakes?

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lake Lake Ann in North Cascades National Park, Washington, U.S., viewed from the park's Maple Loop Trail. The North Cascades National Park is a large wilderness area that preserves majestic mountain scenery, snowfields, glaciers, and other unique natural features.

In freshwater lakes, the plankton community is composed of three primary groups of organisms:

Phytoplankton: These are microscopic, free-floating primary producers that inhabit the upper, sunlit photic zone of the lake. They include algae, cyanobacteria, and various photosynthetic bacteria.1
Zooplankton: These are small, drifting animals that serve as consumers within the lake's food web. They include various small invertebrates, such as rotifers, which can be present in vast numbers during warmer seasons.12
Microbes: In addition to plants and animals, the plankton community includes various microbes that play essential roles in the ecosystem's nutrient cycling and decomposition processes.13

These organisms are fundamental to the lake's trophic levels, with phytoplankton producing biochemical energy through photosynthesis, which is then consumed by zooplankton or broken down by bacteria.13