Tendrils of Cucurbita and thorns of Bougainvillea are

Options

A. Homologous organs
B. Analogous organs
C. Vestical organs
D. Atavistic divergence.

Answer

To answer the question regarding the tendrils of Cucurbita and the thorns of Bougainvillea, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Structures**:
- The tendrils of Cucurbita (commonly known as squash or pumpkin) and the thorns of Bougainvillea are both plant structures.

2. **Determine the Origin**:
- Both tendrils and thorns arise from the axil of the leaves. This indicates that they have a common origin.

3. **Analyze the Functions**:
- The primary function of the tendrils in Cucurbita is to assist in climbing, allowing the plant to support itself as it grows.
- The thorns in Bougainvillea serve a protective function, deterring herbivores and protecting the plant from potential threats.

4. **Compare Origin and Function**:
- Since both structures have the same origin (axillary branches) but serve different functions (climbing vs. protection), they are classified based on their evolutionary relationship.

5. **Classify the Structures**:
- Structures that have a similar origin but different functions are referred to as homologous organs. This indicates that they evolved from a common ancestor but adapted to perform different roles.

6. **Conclusion**:
- Therefore, the tendrils of Cucurbita and the thorns of Bougainvillea are homologous organs.

### Final Answer:
The tendrils of Cucurbita and the thorns of Bougainvillea are **homologous organs**.

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