The four wholes of a flower are arranged on the

Options

A. Thalamus
B. Petiole
C. Corolla
D. Stamens

Answer

To answer the question "The four whorls of a flower are arranged on the:", we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Four Whorls of a Flower**:
- The four whorls of a flower include:
- **Sepals** (calyx)
- **Petals** (corolla)
- **Androecium** (male reproductive part)
- **Gynoecium** (female reproductive part)

2. **Understand the Arrangement of the Whorls**:
- These whorls are arranged on a specific structure of the flower.

3. **Identify the Structure that Holds the Whorls**:
- The structure that holds or supports these floral parts is called the **thalamus** or **receptacle**.

4. **Evaluate the Options Given**:
- The options provided are:
- A) Thalamus
- B) Petiole
- C) Corolla
- D) Stem

5. **Analyze Each Option**:
- **Thalamus**: Correct, as it is the part where all floral whorls are attached.
- **Petiole**: Incorrect, as it connects the leaf to the stem, not the flower.
- **Corolla**: Incorrect, as this refers specifically to the petals, which are part of the flower, not the structure that holds them.
- **Stem**: Incorrect, as it is the main support of the plant but does not specifically hold the floral whorls.

6. **Conclusion**:
- The correct answer is **Thalamus** (or receptacle), as it is the structure that supports and arranges the four whorls of a flower.

### Final Answer:
The four whorls of a flower are arranged on the **thalamus**.

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