Organisms that live in water are called aquatic organisms.

Aquatic organisms are those organisms that have adapted to living in water. They can be found in various aquatic environments such as freshwater bodies like rivers, lakes, and ponds, as well as in marine environments such as oceans and seas. These organisms have specific adaptations that allow them to survive and thrive in their aquatic habitats.

Types of Aquatic Organisms:

There are various types of aquatic organisms, including:

1. Fish: Fish are vertebrates that have adapted to living in water. They have gills that allow them to extract oxygen from water, and fins that help them swim. Fish can be found in both freshwater and marine environments.

2. Amphibians: Amphibians are cold-blooded vertebrates that spend part of their lives in water and part on land. Examples of amphibians include frogs, toads, and salamanders. They have adaptations such as permeable skin and webbed feet to survive in both aquatic and terrestrial habitats.

3. Reptiles: Some reptiles, like turtles and crocodiles, are adapted to live in water. They have streamlined bodies, webbed feet, and other adaptations that help them move and survive in aquatic environments.

4. Invertebrates: Many invertebrates live in water, including insects, crustaceans, mollusks, and worms. These organisms have various adaptations to live in water, such as gills or other respiratory structures.

5. Plants: Aquatic plants, such as algae, seaweed, and water lilies, also live in water. They have adaptations such as floating leaves or specialized structures to absorb nutrients from water.

6. Microorganisms: Microscopic organisms like bacteria, protozoa, and plankton are also found in water. They play crucial roles in the aquatic ecosystem, such as recycling nutrients and serving as food for other organisms.

Adaptations of Aquatic Organisms:

Aquatic organisms have various adaptations to live in water, including:

- Gills: Gills are respiratory organs that allow organisms to extract oxygen from water. They are found in fish, crustaceans, and some amphibians.

- Streamlined Bodies: Many aquatic organisms have streamlined bodies that reduce drag and help them move efficiently through water. This adaptation is particularly important for fast-swimming fish and marine mammals.

- Webbed Feet: Some organisms, like amphibians and aquatic birds, have webbed feet that help them swim or move through water.

- Permeable Skin: Some amphibians have permeable skin that allows them to extract oxygen from water.

- Specialized Reproductive Strategies: Some aquatic organisms have unique reproductive strategies, such as laying eggs in water or having external fertilization, to ensure the survival of their offspring.

- Camouflage: Many aquatic organisms have adaptations to blend in with their surroundings, such as the coloration and patterns of fish and invertebrates.

- Buoyancy Control: Some aquatic organisms, like fish, have swim bladders or other adaptations to control their buoyancy in water.

In conclusion, aquatic organisms are those