Movement of sperms towards archegonial necks due to component of their exudate is

Options

A. Chemotropism
B. Chemotaxis
C. Phototaxis
D. Hydrotropism.

Answer

To solve the question regarding the movement of sperms towards archegonial necks due to components of their exudate, we can analyze the options provided step by step.

### Step-by-Step Solution:

1. **Understanding the Question**:
- The question asks about the type of movement exhibited by sperm towards the archegonial necks, which are structures in certain plants where fertilization occurs.

2. **Analyzing the Options**:
- **Option A: Chemotropism**:
- Definition: Chemotropism refers to the growth of organisms in response to chemical stimuli.
- Conclusion: This option is incorrect because it describes growth, not movement.

- **Option B: Chemotaxis**:
- Definition: Chemotaxis is the movement of an organism in response to a chemical stimulus.
- Conclusion: This option is correct because it specifically describes the movement of sperm towards the archegonial necks due to the chemical components in the exudate.

- **Option C: Phototaxis**:
- Definition: Phototaxis refers to the movement of organisms in response to light.
- Conclusion: This option is incorrect because the question pertains to chemical stimuli, not light.

- **Option D: Hydrotropism**:
- Definition: Hydrotropism is the growth or movement of plant roots towards or away from moisture.
- Conclusion: This option is also incorrect as it relates to moisture and not to the movement of sperm.

3. **Final Conclusion**:
- After analyzing all the options, the correct answer is **Chemotaxis**, as it accurately describes the movement of sperm towards the archegonial necks due to chemical stimuli.

### Final Answer:
The movement of sperms towards archegonial necks due to components of their exudate is **Chemotaxis**.

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