(a) Taking an example of a small pond, explain how the four components of an ecosystem function as a unit.
(b) Name the type of food chain that exists in a pond.

Explanation

### Step-by-Step Solution:

#### (a) Explanation of the Four Components of an Ecosystem in a Small Pond:

1. **Producers**: In a small pond ecosystem, the primary producers are phytoplankton. These are microscopic plants that use sunlight to perform photosynthesis, converting light energy into chemical energy in the form of glucose. They form the base of the food web.

2. **Primary Consumers**: The next level in the food chain consists of primary consumers, which in this case are zooplankton. Zooplankton feed on phytoplankton, thus transferring the energy stored in the producers to the next trophic level.

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