Plankton

Plankton are a diverse group of organisms that live in large bodies of water and are unable to swim against the current. The name "plankton" comes from the Greek word "planktos," meaning "drifter" or "wanderer." Plankton form the base of many aquatic food webs, serving as a critical food source for larger organisms.

There are two primary categories of plankton: phytoplankton and zooplankton.

• Phytoplankton: These are plant-like plankton that, like terrestrial plants, perform photosynthesis. They are autotrophic, meaning they produce their own food using sunlight, water, and carbon dioxide. Phytoplankton include various types of algae, such as diatoms, dinoflagellates, and cyanobacteria. They are responsible for a significant portion of the Earth's oxygen production.

• Zooplankton: These are animal-like plankton that consume other plankton or organic matter. They are heterotrophic, meaning they obtain their food from other sources. Zooplankton include small crustaceans (e.g., copepods, krill), larval stages of larger animals (e.g., fish larvae, crab larvae), and protozoa. They play a vital role in transferring energy from phytoplankton to higher trophic levels.

Plankton are not a taxonomic group but rather an ecological grouping based on lifestyle. Organisms classified as plankton range in size from microscopic bacteria to relatively large jellyfish. Their distribution is influenced by factors such as sunlight availability, nutrient levels, water temperature, and currents. Plankton blooms, which are rapid increases in plankton populations, can occur under favorable conditions and can have significant impacts on aquatic ecosystems. These blooms can sometimes be harmful, producing toxins that affect marine life and human health (Harmful Algal Blooms or HABs). The study of plankton is essential for understanding ocean health, climate change, and the dynamics of aquatic ecosystems.