A flower which can be divided into two equal halves by only one plane is

Options

A. Zygomorphic
B. Actinomorphic
C. perfect
D. Regular

Answer

To determine the type of flower that can be divided into two equal halves by only one plane, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Flower Symmetry**:
- Flowers can be classified based on their symmetry. The two main types are:
- **Actinomorphic (Regular)**: Can be divided into two equal halves by multiple planes.
- **Zygomorphic (Irregular)**: Can be divided into two equal halves by only one specific plane.

2. **Identifying the Correct Term**:
- The question specifies that the flower can only be divided into two equal halves by one plane. This characteristic aligns with the definition of a **zygomorphic flower**.

3. **Eliminating Incorrect Options**:
- **Actinomorphic**: This type allows division into equal halves by any plane, which does not meet the criteria given in the question.
- **Perfect Flower**: This term refers to a flower that contains both male (androecium) and female (gynoecium) reproductive structures, but does not relate to symmetry.
- **Regular Flower**: This is synonymous with actinomorphic and thus also does not fit the criteria.

4. **Conclusion**:
- Based on the definitions and the characteristics of the flowers, the correct answer to the question is that a flower which can be divided into two equal halves by only one plane is called a **zygomorphic flower**.

### Final Answer:
The flower which can be divided into two equal halves by only one plane is known as a **zygomorphic flower**.

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