Four chambered is characteristic of poikilotherm

Options

A. Psittacula
B. Hemidactylus
C. Pteropus
D. Crocodilus

Answer

**Step-by-Step Solution:**

1. **Understanding the Terms:**
- **Four-Chambered Heart:** This refers to a heart structure that consists of two atria (auricles) and two ventricles. This type of heart is typically found in birds and mammals.
- **Poikilotherm:** This term describes animals that cannot regulate their body temperature internally and are often referred to as "cold-blooded." Examples include reptiles, amphibians, and fish.

2. **Identifying the Options:**
- The question presents four options, and we need to determine which one has a four-chambered heart and is also a poikilotherm.

3. **Analyzing Each Option:**
- **Option 1: Cetacula (Parakeet):** Parakeets are birds and have a four-chambered heart. However, they are homeothermic (warm-blooded), so this option is incorrect.
- **Option 2: Hemidectylus (Wall Lizard):** This is a reptile and is poikilothermic, but it has a three-chambered heart, so this option is also incorrect.
- **Option 3: Bat:** Bats are mammals and have a four-chambered heart. They are also homeothermic, making this option incorrect.
- **Option 4: Crocodilus (Crocodile):** Crocodiles are reptiles and are poikilothermic. They are unique among reptiles because they possess a four-chambered heart, making this option correct.

4. **Conclusion:**
- The correct answer is **Crocodilus (Crocodile)**, as it is the only poikilotherm with a four-chambered heart.