A flower represents a complex array of functionally specialised structures that differ substantially from vegatative plant body in form and cell types. Select the statement that is not true with regard to floral meristems.

Options

A. Floral meristems are larger in size than the vegetative meristems.
B. Increase in size of the floral meristem is due to larger size of the cells which in turn result from rapid cell expansion only.
C. Increase in size of the floral meristem is largely are result of increased rate of cell division in central cells.
D. A floral morphogeesis is controlled by a network of genes in plants.

Explanation

To solve the question regarding floral meristems, we will go through the provided statements and evaluate their truthfulness step by step.

### Step-by-Step Solution:

1. **Understand the Concept of Meristems**:
- Meristems are regions in plants where cells continuously divide, leading to growth. They are responsible for the formation of new tissues and organs.

2. **Identify Types of Meristems**:
- There are two main types of meristems:
- **Vegetative Meristems**: Responsible for the growth of leaves and stems.
- **Floral Meristems**: Responsible for the development of flowers.

3. **Analyze the Statements**:
- We need to evaluate the statements provided in the question regarding floral meristems.

4. **Evaluate Each Statement**:
- **Option A**: "Floral meristems are larger in size than the vegetative meristems."
- This statement is generally true as floral meristems tend to be larger due to their role in flower formation.

- **Option B**: "Increase in size of the floral meristem is due to the large size of the cells which in turn result from the rapidly cell expansion only."
- This statement is **not true**. The increase in size of the floral meristem is primarily due to an increase in the rate of cell division, not just cell expansion.

- **Option C**: "The increase in size of the floral meristem is largely the result of increased rate of cell divisions in the central cell."
- This statement is true. The growth of the floral meristem is largely due to increased cell division.

- **Option D**: "Floral morphogenesis is controlled by the network of genes in plants."
- This statement is also true. The development of flowers is regulated by genetic factors.

5. **Conclusion**:
- The statement that is **not true** regarding floral meristems is **Option B**.

### Final Answer:
The statement that is not true with regard to floral meristems is **Option B**.

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