An infloresence having sessile flowers, a flattened receptacle and an involurce of bracts is

Options

A. capitulum
B. hypanthodium
C. umbel
D. spikelet

Answer

To solve the question about identifying the type of inflorescence characterized by sessile flowers, a flattened receptacle, and an involucre of bracts, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Terms**:
- **Inflorescence**: A cluster of flowers arranged on a stem.
- **Sessile Flowers**: Flowers that do not have a stalk (pedicel) and are directly attached to the receptacle.
- **Flattened Receptacle**: The part of the stem that supports the flowers, which is flattened in this case.
- **Involucre**: A whorl of bracts (leaf-like structures) that surrounds the flower cluster.

2. **Identify the Characteristics**:
- The inflorescence has **sessile flowers**, meaning they are directly attached to the receptacle without any stalks.
- The **receptacle is flattened**, which is a key feature of certain types of inflorescences.
- There is an **involucre of bracts**, indicating that there are leaf-like structures surrounding the flowers.

3. **Recall Inflorescence Types**:
- Common types of inflorescence include raceme, spike, umbel, and capitulum.
- Among these, the **capitulum** is known for having a flattened receptacle and sessile flowers.

4. **Connect Characteristics to Inflorescence Type**:
- The capitulum is characterized by a flattened receptacle that bears many small, sessile flowers.
- It often has an involucre of bracts surrounding the flower cluster, which matches the description given in the question.

5. **Conclude the Answer**:
- Based on the characteristics described, the correct answer to the question is **Capitulum**. This type of inflorescence is commonly found in the family Compositae (Asteraceae), with examples including sunflowers and cosmos.

### Final Answer:
The inflorescence having sessile flowers, a flattened receptacle, and an involucre of bracts is called **Capitulum**.

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