Phytoplankton and Zooplankton

Phytoplankton and Zooplankton are very similar in terms of their habitat, eating habits, and reproduction. They are also fairly easy to distinguish visually. Both Zooplankton and Phytoplankton inhabit the ocean surface and chow down on algae found near the water’s surface. The main difference between these two groups is that Zooplankton are small enough for fish to eat them, while this is not true for Phytoplankton as they are too large for most fish to catch.

What is Phytoplankton?

Phytoplankton (Greek – “plant parts”) is a microscopic plant that resides on the ocean’s surface. Phytoplankton are tiny microorganisms (tiny life forms) that exist in ocean waters, lakes, and ponds. These tiny organisms are able to absorb carbon dioxide from the environment and release oxygen back into the atmosphere. This process is also known as photosynthesis and is thus an important life source for all other plants on Earth. Phytoplankton has been classified into a number of different groups based on their biological characteristics, life cycle, and genetics.

Significance of Phytoplankton

Phytoplankton are a crucial part of the marine food chain. The food chain is the process where marine organisms consume one another for their nutrition, and in turn are consumed by yet other marine animals. Phytoplankton help build up the food chain by providing their edible protein to cod, salmon, crab, shrimp, shellfish, and many others. Additionally, phytoplankton also regulate the oceans’ carbon cycle. Phytoplankton take in carbon dioxide from outside through photosynthesis and release oxygen back into the atmosphere where it is removed from greenhouse gases by plants such as trees.

What is Zooplankton?

Zooplankton (Greek – “sea animals”) are very small marine organisms, which include shellfish, crustaceans, and mollusks. These little creatures are able to feed on phytoplankton and other marine organisms such as krill or zooplankton. Zooplankton either search for phytoplankton by swimming through the water or feed on other zooplankton using their pincers like mouth parts. Zooplankton is also eaten by many animals ranging from fish to birds. In fact, the survival and development of many marine animals depend on zooplankton.

Phytoplankton and Zooplankton: Difference

1. Both phytoplankton and zooplankton are microscopic organisms found on the ocean’s surface.
2. Phytoplankton and zooplankton resemble their larger counterparts, fish, crustaceans, and mollusks in many ways. In fact, they have few different structures when compared to those marine organisms.
3. Both phytoplankton and zooplankton grow by feeding on bacteria, algae, and other microorganisms. They help keep the ocean environment clean because they consume anything that may harm other marine life such as krill or jellyfish.
4. While phytoplankton are too large for most fish to consume, zooplankton is small enough to be eaten by fish.
5. Zooplankton either swim or crawl around the ocean’s surface for phytoplankton and other zooplankton to consume, while phytoplankton float on the surface of water.
6. Phytoplankton have been classified into different groups based on their phenotypic characteristics such as color and habitat; however, there are no distinct classes of zooplanktons. Each zooplankton is categorized based on its own unique features.
7. Phytoplankton are eaten by many other organisms ranging from fish to crustaceans to marine birds. Zooplankton, on the other hand, are only consumed by these same organisms.
8. Phytoplankton help regulate the carbon cycle in the oceans, helping absorb greenhouse gases from the outside environment and releasing oxygen back into the atmosphere. While zooplankton also help in this process by consuming phytoplankton and bacteria, they do not have any significant role in the carbon cycle like phytoplanktons do with their photosynthesis process.
9. One important difference between the two groups of marine organisms is the size of their body. Zooplankton are small enough to be consumed by fish while phytoplankton remain too large for a fish to catch.
10. Phytoplankton are also known as microalgae while zooplankton are called macrozooplankton. Both contain different nutrients that affect the growth and development of other marine life. 
11. Phytoplankton does not have any eyes like other creatures, but you can often see them with a magnifying glass if you look closely enough in the water; however, zooplanktons do have two eyes like most animals on land do.

Conclusion

Phytoplankton and zooplankton are vital components of the marine food chain. These tiny organisms provide their edible protein to creatures higher up on the food chain, which in turn are eaten by larger marine animals. Phytoplankton and zooplankton also help with the carbon cycle by exchanging carbon dioxide to oxygen in the atmosphere and vice versa. Phytoplanktons are critical to maintaining acceptable carbon dioxide concentrations in aquatic life, while zooplanktons help clean up the environment by eating things that might harm other marine organisms, such as krill or jellyfish.