Difference Between Phytoplankton and Zooplankton

Main Difference

The main difference between Phytoplanktons and Zooplankton is that Phytoplanktons are a photosynthetic, microscopic organisms live in rivers, lakes, freshwater, and streams whereas Zooplanktons are small aquatic animals that also live in water bodies, but they cannot make their own food, and they are dependent on phytoplankton.

Phytoplankton vs. Zooplankton

Phytoplanktons are in fact plants while zooplanktons are animals. Phytoplanktons synthesize their food in the presence of direct sunlight and also depended on minerals whereas zooplanktons use phytoplankton and other small and large zooplankton as their food. Phytoplankton acts as a primary producer in the aquatic food chains while zooplanktons are known as consumers. Phytoplanktons prepare their food either by photosynthesis or chemosynthesis while zooplanktons cannot make their food. Phytoplankton releases a lot of oxygen in the water on the other hand zooplanktons do not release oxygen. Phytoplankton uses sunlight for their food, so they prefer to live near the surface of the water where there is plenty of the sunlight, on the other hand, zooplankton always lives in the deeper parts of the sea where there is no sunlight and travel to the surface during the night to feed.

Comparison Chart

PhytoplanktonZooplankton
Phytoplankton are photosynthetic microscopic autotrophic organismsZooplanktons are heterotrophic organisms
Etymology
This name comes from the Greek word phyton meaning “plant.The name zooplankton is derived from Greek meaning “animal.”
Feeding
They prepare their own food in the presence of sunlightThey feed on bacterioplankton and other species of zooplankton
Habitat
Phytoplanktons live near the surface of water bodiesThey live in colder and darker places of oceans and water bodies
Movement
They cannot moveThey can move freely
Ecological Importance
They serve as food for marine organisms and keep the stability of marine lifeThey help in checking the toxicity level of the waterbody
Examples
Algae, blue-green algae, flagellates and diatomsCrustaceans, radiolarians, ctenophores, krill, and mollusks

What is Phytoplankton?

Phytoplankton is the photosynthesizing microscopic organisms, found in the sunny upper layer of all the oceans. This name comes from the Greek word phyton meaning plant. They are also the primary producers of marine life; they obtain their energy from the direct sunlight and prepare food by photosynthesis. Like all other plants, they use sunlight, carbon dioxide, and other nutrients and convert them into carbohydrates and oxygen. They serve as food for marine individuals and keep the stability of marine life. Phytoplankton is the primary source to produce about 50% oxygen of the marine ecosystem as they release oxygen in the result of photosynthesis. They also vary in different sizes as they consist of unicellular organisms to organisms that are found in colonies. Sometimes they are known as grasses of seas. They play a role in food chains. Phytoplankton exists in varying size; they can be so tiny that one can not see with a naked eye and they can be large too.

Examples

Algae like blue-green algae and diatoms, dinoflagellates, cryptomonads, true flagellates, and green algae.

What is Zooplankton?

Zooplanktons are small aquatic animals living in the freshwater streams and lakes. The name zooplankton is derived from the Greek word meaning animal. They all are moveable. Zooplanktons are categorized into two categories. One is holoplankton, and the other is meroplankton. Holoplankton contains permanent zooplanktons like polychaetes, larvaceans, copepods, etc. Meroplankton includes the temporary planktons for example crustaceans, mollusks, and some small fishes. Some of them have the ability to swim against the water flow like jellyfish and combfish. The size of zooplankton can vary from microscopic to more massive than a human being. They help in checking the toxicity level of the waterbody. They also play an important role in aquatic food webs as a resource for other consumers. Zooplankton exists in varying size; they can be so small that one can not see with a naked eye and they can be large too.

Examples

Radiolarians, foraminiferans, crustaceans, ctenophores called comb jellyfish, rotifers, mollusks, and dinoflagellates.

Key Differences

  1. Phytoplanktons are plants and known as plant drifter, on the other side zooplankton is an animal
  2. Phytoplankton is known as autotrophs as they can make their food while zooplankton is known as the heterotrophs as they can not prepare their own
  3. Phytoplankton cannot move freely whereas zooplankton can move freely.
  4. Phytoplankton is directly dependent on plants while zooplankton depends on phytoplankton and other zooplankton.
  5. Phytoplankton found on the upper surface of the water where they get enough light while zooplanktons prefer darker and cool places.
  6. Phytoplanktons release oxygen in the water on the other hand zooplanktons do not release oxygen.

Comparison Video

YouTube video

Conclusion

Conclusion of this article is that planktons consist of phytoplankton and zooplankton in which “Phyto” means plant and “zoo” means animal. Phytoplankton is freshwater and marine plants, and zooplankton is marine animals. Some planktonic organisms are neither plants nor animals, so they are known as protists. Both are very important for the stability of marine life. Both help in checking the health of the water body.

Janet White

Janet White is a writer and blogger for Difference Wiki since 2015. She has a master's degree in science and medical journalism from Boston University. Apart from work, she enjoys exercising, reading, and spending time with her friends and family. Connect with her on Twitter @Janet__White

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