In most of the brown algae asexual reproduction takes place by -

Options

A. Auxospores
B. Aplanospores
C. Pear shaped /pyriform biflagellate zoospores (have lateral, unequal flagella)
D. Multiflagellate zoospore

Answer

**Step-by-Step Solution:**

1. **Identify the Type of Algae**: The question focuses on brown algae, which belong to the class Phaeophyceae.

2. **Understand Asexual Reproduction**: Asexual reproduction in algae can occur through various methods, including fragmentation, spore formation, and others.

3. **Focus on Brown Algae**: In brown algae, the primary method of asexual reproduction is through the formation of zoospores.

4. **Define Zoospores**: Zoospores are motile spores that can swim due to the presence of flagella.

5. **Characteristics of Brown Algal Zoospores**: The zoospores in brown algae are specifically described as biflagellated, meaning they have two flagella.

6. **Shape and Flagella Arrangement**: The zoospores are pear-shaped (or pyriform) and possess two unequal flagella that are laterally attached.

7. **Conclusion**: Therefore, in most brown algae, asexual reproduction takes place by biflagellated zoospores that are pear-shaped with laterally attached unequal flagella.

**Final Answer**: In most brown algae, asexual reproduction takes place by biflagellated zoospores, which are pear-shaped and have laterally unequal flagella.

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