In Spirogyra, asexual reproduction takes place by

Options

A. breaking up of filaments into smaller bits
B. division of a cell into two cells
C. division of a cell into many cells
D. formation of young cells from older cells

Explanation

**Step-by-Step Solution:**

1. **Understanding Spirogyra**: Spirogyra is a filamentous green algae that reproduces both sexually and asexually. In this case, we are focusing on asexual reproduction.

2. **Identifying Asexual Reproduction Method**: Asexual reproduction in Spirogyra occurs when the mature parent filament breaks into smaller fragments.

3. **Fragmentation Process**: When the parent Spirogyra filament matures, it undergoes fragmentation. This means it breaks up into smaller pieces or fragments.

4. **Growth of Fragments**: Each of these smaller fragments can grow independently to form a new individual Spirogyra. This means that each fragment has the potential to develop into a complete organism.

5. **Selecting the Correct Option**: Given the options:
- a. Breaking up of filament into smaller bits
- b. Division of a cell into two cells
- c. Division of a cell into many cells
- d. Formation of young cells from the older cells
The correct answer is **option A**, as it accurately describes the process of asexual reproduction in Spirogyra.

**Final Answer**: In Spirogyra, asexual reproduction takes place by **breaking up of filament into smaller bits** (Option A).

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