Question

A fish living in a pond ecosystem feeds on small aquatic insects (larvae). These insect larvae, in turn, feed on green algae and small photosynthetic bacteria.
In this specific food chain, what is the trophic level classification of fish?

• A. Producer
• B. Primary Consumer
• C. Secondary Consumer
• D. Tertiary Consumer

Hint:

Write the food chain from producer to fish and count the levels. Algae is level 1.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
A food chain shows who eats whom. Each step is a trophic level. Producers make their own food. Primary consumers eat producers. Secondary consumers eat primary consumers. Tertiary consumers eat secondary consumers.

Step 2: Build the chain from the passage:
Green algae and photosynthetic bacteria make food using sunlight, so they are PRODUCERS (level 1). Insect larvae eat them, so larvae are PRIMARY CONSUMERS (level 2). The fish eats the larvae, so the fish is a SECONDARY CONSUMER (level 3).

Step 3: Write the chain:
\[ \text{Green algae} \to \text{Insect larvae} \to \text{Fish} \]

Step 4: Why the other options are wrong:
(A) Producer: the fish cannot make its own food.
(B) Primary consumer: the fish does not eat the algae directly. It eats larvae.
(D) Tertiary consumer: this would need one more consumer below the fish, and none is given.

Final Answer:
The fish feeds on primary consumers, so it is a secondary consumer. This is option (C). \[ \boxed{\text{C}} \]