What is plankton ?

Options

A. Pond scum
B. Floating vegetation
C. Benthic organisms
D. Floating microscopic plants and animals

Answer

**Step-by-Step Solution:**

1. **Definition of Plankton**: Plankton are small organisms that live in water and are unable to swim against the current. They are typically microscopic and can be found in both freshwater and marine environments.

2. **Types of Plankton**: Plankton can be divided into two main categories:
- **Phytoplankton**: These are the plant-like organisms that perform photosynthesis. They are primarily microscopic algae and are crucial for producing oxygen and serving as the base of the aquatic food web.
- **Zooplankton**: These are the animal-like organisms that feed on phytoplankton and other small particles in the water. They can be microscopic or small enough to be seen with the naked eye.

3. **Importance of Plankton**: Plankton play a vital role in aquatic ecosystems. They are essential for nutrient cycling, serving as a food source for a variety of marine animals, including fish and whales. They also contribute to the oxygen supply in the water.

4. **Conclusion**: Based on the definitions and types, plankton are indeed floating microscopic plants and animals, making them a crucial component of aquatic ecosystems.

**Final Answer**: Plankton are floating microscopic plants and animals, including phytoplankton (plant-like) and zooplankton (animal-like).

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