When micropyle, chalaza and hilum lie in a straight line, the ovule is said to be

Options

A. anatropous
B. orthotropous
C. amphitropous
D. campylotropous

Explanation

**Step-by-Step Solution:**

1. **Understanding the Terms:**
- **Micropyle:** The opening in the ovule through which the pollen tube enters.
- **Chalaza:** The part of the ovule opposite the micropyle, where the ovule attaches to the ovary wall.
- **Hilum:** The scar on the seed where it was attached to the ovule.

2. **Identifying the Types of Ovules:**
- There are four main types of ovules based on the arrangement of the micropyle, chalaza, and hilum:
- **Anatropous:** The ovule is inverted, with the micropyle close to the funicle.
- **Orthotropous:** The micropyle, chalaza, and hilum are aligned in a straight line.
- **Amphitropous:** The ovule is curved, but the micropyle and chalaza are not in a straight line.
- **Campylotropous:** The ovule is curved, with the micropyle and chalaza not aligned.

3. **Analyzing the Question:**
- The question asks for the type of ovule where the micropyle, chalaza, and hilum are in a straight line.

4. **Identifying the Correct Answer:**
- In the **orthotropous** condition, the micropyle, chalaza, and hilum are indeed in a straight line. This is the only type that meets the criteria given in the question.

5. **Conclusion:**
- Therefore, the correct answer to the question is **orthotropous**.

**Final Answer:** The ovule is said to be **orthotropous** when the micropyle, chalaza, and hilum lie in a straight line.

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