All species of plankton have adaptations that include flat bodies, lateral spines, oil droplets and floats filled with gas. Other adaptations include sheaths that are made of a gel-like substance and ion replacement. These structural adaptations allow plankton to float in the water column easily without sinking to the bottom.
The flat bodies and spines that some species of plankton have allow them to increase the surface area of their bodies when needed while simultaneously decreasing their volume. This allows them to resist sinking. Plankton are any organisms that float in the water as opposed to swimming in the water. This includes zooplankton, which are animal-based, and phytoplankton, which are plant based. Both types of plankton are very weak swimmers, so they typically flow with the current and tides.
Zooplankton also have specific adaptations that help them escape from and deter fish. These include transparent bodies, bright colors, bad tastes, red coloring in deeper water and cyclomorphosis. Zooplankton use cyclomorphosis to increase their spines and protective shields. This response is signalled when a predator releases specific chemicals, such as rotifers or cladocerans, into the surrounding water.
Phytoplankton contain chloroplasts just like plants, which gives them their green coloring. They also use sunlight and other nutrients to complete the process of photosynthesis to feed themselves like plants. In addition to this, they serve as a source of food for zooplankton.