Which of the following is not an example of homologous organ?

Options

A. Vertebrate hearts or brains
B. Thorns of Bougainvillea and tendrils of Cucurbita
C. Leg of Cheetah, and flipper of whale
D. Eye of octopus and of mammals

Answer

To determine which of the following is not an example of homologous organs, we first need to understand what homologous organs are.

### Step-by-Step Solution:

1. **Definition of Homologous Organs**: Homologous organs are those that have a similar origin (common ancestry) but may serve different functions in different organisms.

2. **Analyzing the Options**:
- **Option 1: Vertebrate Heart and Brain**:
- The heart and brain do not share a common function. The heart is responsible for pumping blood, while the brain is involved in processing information and controlling bodily functions. Therefore, they are not homologous organs.

- **Option 2: Thorns of Wagonvilla and Tendril of Cucurbita**:
- Both thorns and tendrils have evolved from the same ancestral structure but serve different functions (protection vs. support). Hence, they are homologous organs.

- **Option 3: Leg of Cheetah and Flipper of Whale**:
- Both structures have a common origin but serve different functions (running vs. swimming). Therefore, they are homologous organs.

- **Option 4: Eye of Octopus and Eye of Mammal**:
- The eyes of octopus and mammals have evolved independently to serve similar functions (vision) but do not share a common origin. Therefore, they are not homologous organs.

3. **Conclusion**:
- The correct answer to the question "Which of the following is not an example of homologous organ?" is **Option 1: Vertebrate Heart and Brain**.