The four whorls of the flower arrange on

Options

A. ovaries
B. petals
C. stem
D. thalamus

Answer

To answer the question regarding the arrangement of the four whorls of a flower, we can break it down into a step-by-step solution:

### Step-by-Step Solution:

1. **Identify the Four Whorls of a Flower**:
- The four whorls of a flower consist of:
- **Sepals**: The outermost whorl, usually green, which protects the flower bud.
- **Petals**: The second whorl, often colorful, which attracts pollinators.
- **Stamens**: The third whorl, the male reproductive part, which produces pollen.
- **Carpels (or Pistils)**: The innermost whorl, the female reproductive part, which contains the ovary.

2. **Understand the Arrangement**:
- The arrangement of these whorls is crucial for the flower's structure and function. They are typically arranged in a circular pattern around a central point.

3. **Identify the Support Structure**:
- The whorls are arranged on a part of the flower known as the **thalamus** or **receptacle**. This is the thickened part of the stem where the flower parts are attached.

4. **Conclusion**:
- Therefore, the four whorls of the flower are arranged on the **thalamus** (receptacle).

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

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