Which of the following animal is cold blooded and has 4 - chambered heart

Options

A. Salamander
B. Ornithorhynchus
C. Crocodile
D. Calotes

Answer

To solve the question of which animal is cold-blooded and has a four-chambered heart, we can analyze each option provided:

### Step-by-Step Solution:

1. **Identify the Characteristics of Cold-Blooded Animals**:
- Cold-blooded animals, also known as ectothermic animals, are those whose body temperature is regulated by the external environment. They include reptiles, amphibians, and fish.

2. **Understand the Structure of the Heart**:
- A four-chambered heart consists of two atria and two ventricles. This structure is typically found in birds and mammals, but there are exceptions in some reptiles.

3. **Evaluate Each Option**:
- **Option 1: Salamander**:
- Salamanders are amphibians and have a three-chambered heart (two atria and one ventricle). Therefore, this option is incorrect.

- **Option 2: Ornithorhynchus (Platypus)**:
- The platypus is a mammal and has a four-chambered heart. However, it is warm-blooded, not cold-blooded. Thus, this option is also incorrect.

- **Option 3: Crocodile**:
- Crocodiles are reptiles and are known to be cold-blooded. They are unique among reptiles because they possess a four-chambered heart, consisting of two atria and two ventricles. This makes this option correct.

- **Option 4: Calotus (Lizard)**:
- Lizards are also reptiles and have a three-chambered heart. Therefore, this option is incorrect.

4. **Conclusion**:
- The only animal that is cold-blooded and has a four-chambered heart is the **Crocodile**.

### Final Answer:
Crocodile is the animal that is cold-blooded and has a four-chambered heart.

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