The condition is called phytoplankton because algae are microscopic, need sunlight and nutrient, water to survive.
Phytoplankton refers to microscopic marine algae and they are also called microalgae.They are similar to terrestrial plants in that they contain chlorophyll and require sunlight in order to live and grow. Most phytoplankton are very buoyant and float in the upper part of the ocean, where sunlight enter the water and they get the sunlight to produce food.
Algae photosynthesized,that is they use sunlight in the presence of chlorophyii and carbondioxide to produce food and oxygen.
Therefore, The condition is called phytoplankton because algae are microscopic, need sunlight and nutrient, water to survive.
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