Maximum absorption of sunlight Stay near surface Maximize surface area 2. Reproduce quickly when nutrients available 3. Evade predators by feeding at night 2.
Plankton have limited control on their individual movement.
Phytoplanktonic algae are photosynthetic, and their taxonomic subdivisions are based on the color of their dominant photsynthetic pigment pigment. But some phytoplankton can also be heterotrophic. Phytoplankton play an essential role in the biology of the seas by being the primary producers of food for other organisms. Important Representatives of the Phytoplankton Diatoms . They occur as single cells or as large colonies of cells.