In scalariform conjugation of Spirogyra the fusing gametes are derived from

Options

A. Same filament
B. Two different filaments
C. Both A and B
D. Only one filament is involved in the process.

Answer

**Step-by-Step Solution:**

1. **Understanding Spirogyra**: Spirogyra is a type of green algae that belongs to the phylum Chlorophyta. It is known for its spiral-shaped chloroplasts and is capable of photosynthesis due to the presence of chlorophyll A and B.

2. **Identifying the Reproductive Process**: Spirogyra can reproduce both asexually and sexually. The sexual reproduction can occur through two types of conjugation: lateral conjugation and scalariform conjugation.

3. **Defining Scalariform Conjugation**: In scalariform conjugation, the gametes are formed from two different filaments. This is a key characteristic that distinguishes it from lateral conjugation, where the gametes come from the same filament.

4. **Analyzing the Options**: The question provides several options regarding the origin of the fusing gametes in scalariform conjugation:
- A) Same filament
- B) Two different filaments
- C) Both A and B
- D) Only one filament involved

5. **Evaluating the Options**:
- Option A (Same filament) is incorrect as this pertains to lateral conjugation.
- Option B (Two different filaments) is correct as it describes scalariform conjugation.
- Option C (Both A and B) is incorrect since only one type of filament is used in each type of conjugation.
- Option D (Only one filament involved) is also incorrect as scalariform conjugation specifically involves two filaments.

6. **Conclusion**: The correct answer is option B: the fusing gametes in scalariform conjugation of Spirogyra are derived from two different filaments.

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