Primary consumers in detritus food chain are

Options

A. (a) herbivores
B. (b) bacteria and fungi
C. (c) insect larvae, nematodes
D. (d) all the above

Answer

**Step-by-Step Solution:**

1. **Understanding the Detritus Food Chain (DFC):**
- The detritus food chain begins with dead organic matter, which includes decomposing leaves, dead animals, and other decaying materials. This is the starting point of the DFC.

2. **Identifying the Role of Primary Consumers:**
- In the detritus food chain, primary consumers are organisms that feed on this dead organic matter. They play a crucial role in breaking down and recycling nutrients.

3. **Recognizing Primary Consumers:**
- The primary consumers in the detritus food chain include organisms such as bacteria and fungi, which are known as saprotrophs. They decompose dead organic matter, facilitating nutrient cycling.

4. **Considering Other Organisms:**
- Other organisms that can act as primary consumers in the detritus food chain include certain crustaceans and protozoans. These organisms also feed on dead and decaying matter.

5. **Conclusion:**
- Therefore, the primary consumers in the detritus food chain are primarily bacteria and fungi, along with some crustaceans and protozoans.

**Final Answer:**
Primary consumers in the detritus food chain are bacteria, fungi, crustaceans, and protozoans.

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