Pear shaped gametes with two laterally attached flagella are formed in

Options

A. Polysiphonia
B. Ulothrix
C. Fucus
D. Spirogyra

Answer

To solve the question regarding the formation of pear-shaped gametes with two laterally attached flagella, we can follow these steps:

### Step 1: Identify the Characteristics of the Gametes
The question describes gametes that are pear-shaped (or piriform) and have two flagella attached laterally. This is a specific characteristic that can help us narrow down the options.

### Step 2: Understand the Types of Algae
The options given are:
- Polysiphonia (red algae)
- Ulothrix (green algae)
- Fucus (brown algae)
- Spirogyra (green algae)

We need to identify which of these types of algae is known to produce pear-shaped gametes.

### Step 3: Analyze Each Option
1. **Polysiphonia**: This is a red algae and does not produce pear-shaped gametes.
2. **Ulothrix**: This is a green algae and also does not produce pear-shaped gametes.
3. **Fucus**: This is a brown algae (Phaeophyceae) and is known to produce pear-shaped gametes with two laterally attached flagella.
4. **Spirogyra**: This is also a green algae and does not produce pear-shaped gametes.

### Step 4: Confirm the Characteristics of Fucus
Fucus is known for producing piriform gametes that have:
- Two flagella attached laterally
- One flagellum is longer than the other
- Hair-like structures present on one of the flagella

### Step 5: Conclusion
Based on the analysis, the correct answer is **Fucus**, as it is the only option that matches the description of producing pear-shaped gametes with two laterally attached flagella.

### Final Answer
**Fucus**

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