Find the odd one (w.r.t. inflorescence axis elongation)

Options

A. Umbel
B. Spike
C. Raceme
D. Catkin

Answer

To solve the question of finding the odd one out with respect to inflorescence axis elongation, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Inflorescence Types**:
- Inflorescence can be classified into two main types: Racemose and Cymose.
- Racemose inflorescence has the youngest flowers at the apex and older flowers at the base.

2. **Identify Types of Racemose Inflorescence**:
- Racemose inflorescence can be further categorized based on the elongation of the main axis:
- **Elongated Main Axis**: Examples include spike, catkin, and spadix.
- **Shortened Main Axis**: An example is the humble (also known as umbel).
- **Flattened Main Axis**: An example is capitulum.

3. **Analyze the Given Options**:
- The options provided are:
1. Humble
2. Pipe
3. Resin
4. Kaolin
- We need to determine which of these options does not fit with the others in terms of axis elongation.

4. **Evaluate Each Option**:
- **Humble (Umbel)**: This has a shortened main axis.
- **Pipe**: This is not a standard term in botany for inflorescence, but if we consider it as a type of elongated inflorescence, it could fit.
- **Resin**: This is typically associated with elongated inflorescence.
- **Kaolin**: Similar to pipe, this is not a standard inflorescence type but could imply elongation.

5. **Identify the Odd One Out**:
- Among the options, **Humble** is the only one that represents a type of inflorescence with a shortened main axis, while the others (assuming pipe and kaolin imply elongated types) represent elongated main axes.
- Therefore, **Humble** is the odd one out.

### Final Answer:
The odd one out with respect to inflorescence axis elongation is **Humble**.

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