Pollen tube, after reaching the ovary generally enters the ovule through the

Options

A. nucellus
B. integument
C. chalaza
D. micropyle

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks where the pollen tube enters the ovule after reaching the ovary.

2. **Identifying Key Structures:**
To answer this, we need to identify the relevant structures in the ovary and ovule. The main structures to consider are:
- Micropyle
- Nucellus
- Integuments
- Chalaza

3. **Locating the Micropyle:**
The micropyle is a small opening in the ovule that allows the pollen tube to enter. It is located at one end of the ovule.

4. **Examining Other Options:**
- **Nucellus:** This is the tissue that surrounds the ovule but is not where the pollen tube enters.
- **Integuments:** These are the outer layers of the ovule, providing protection, but the pollen tube does not enter here.
- **Chalaza:** This is the opposite end of the micropyle and does not serve as an entry point for the pollen tube.

5. **Conclusion:**
The pollen tube generally enters the ovule through the **micropyle**. Therefore, the correct answer is the micropyle.

**Final Answer:**
The pollen tube generally enters the ovule through the micropyle.

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