The term prothallus is used for

Options

A. Stage before thallus
B. Plant body without differentiation of stem, leaves and roots
C. Reduced gametophyte
D. Reduced sporophyte.

Answer

**Step-by-Step Solution:**

1. **Understanding the Term "Prothallus":**
- The term "prothallus" refers to a specific stage in the life cycle of certain plants, particularly in the group of plants known as bryophytes and pteridophytes. It is important to clarify what this term signifies in botanical terms.

2. **Identifying the Nature of Prothallus:**
- The prothallus is a gametophyte stage, which means it is the haploid phase of the plant life cycle. This stage is responsible for producing gametes (sperm and eggs).

3. **Analyzing the Options:**
- The question provides several options:
- A) Stage before thallus
- B) Plant body without differentiation of stem, leaves, and roots
- C) Reduced gametophyte
- D) Reduced sporophyte

4. **Evaluating Each Option:**
- A) "Stage before thallus" - This is incorrect as the prothallus is not simply a precursor to a thallus.
- B) "Plant body without differentiation of stem, leaves, and roots" - This is also incorrect. While the prothallus may not have differentiated structures, this definition does not specifically describe the prothallus.
- C) "Reduced gametophyte" - This option is correct. The prothallus is indeed a reduced form of the gametophyte.
- D) "Reduced sporophyte" - This is incorrect as the prothallus is not a sporophyte but rather a gametophyte.

5. **Conclusion:**
- Based on the analysis, the correct answer is **C) Reduced gametophyte**. The prothallus is specifically known as a reduced form of the gametophyte in the life cycle of certain plants.

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