The term phyllotaxy is used to describe

Options

A. type of ovary in a plant
B. mode of arrangement of leaves on the axis or stem
C. the type of roots
D. arrangement of sepals and petals in a flower.

Answer

To solve the question regarding the term "phyllotaxy," we will analyze the options provided and determine the correct definition.

### Step-by-Step Solution:

1. **Understanding the Term**:
- The term "phyllotaxy" refers to the arrangement of leaves on the stem or axis of a plant. This is a key concept in botany.

2. **Analyzing the Options**:
- **Option A**: Type of ovary in a plant.
- This option is incorrect. Phyllotaxy does not relate to the ovary structure.
- **Option B**: Mode of arrangement of leaves on the axis or stem.
- This option is correct. Phyllotaxy specifically describes how leaves are arranged on the stem.
- **Option C**: Types of fruit.
- This option is incorrect. Phyllotaxy does not pertain to fruit classification.
- **Option D**: Arrangement of sepals and petals in a flower.
- This option is also incorrect. The arrangement of floral parts is referred to as "estivation," not phyllotaxy.

3. **Conclusion**:
- Based on the analysis, the correct answer is **Option B: Mode of arrangement of leaves on the axis or stem**.

### Final Answer:
The term phyllotaxy is used to describe the mode of arrangement of leaves on the axis or stem of a plant.

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