Which type of animals have severe effect of change in temperature of environment?

Options

A. Desert animals
B. Aquatic animals
C. Poikilothermal animals
D. Homoiothermal animals

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks which type of animals are severely affected by changes in environmental temperature.

2. **Identifying Animal Types:**
We need to consider different types of animals based on their ability to regulate body temperature. The main categories are:
- Desert animals
- Aquatic animals
- Poikilothermic (cold-blooded) animals
- Homeothermic (warm-blooded) animals

3. **Analyzing Desert and Aquatic Animals:**
- **Desert Animals:** These animals have adaptations that allow them to cope with extreme temperatures, such as burrowing or being active at cooler times of the day. They can regulate their internal temperature to some extent.
- **Aquatic Animals:** Many aquatic animals can also regulate their internal temperature, especially those living in stable environments like deep oceans. Therefore, they are not severely affected by temperature changes.

4. **Examining Poikilothermic Animals:**
- **Poikilothermic Animals:** These are also known as cold-blooded animals. They cannot regulate their body temperature internally and rely on the external environment. This means that if the environmental temperature changes, their body temperature changes accordingly. They are severely affected by extreme temperatures, as they lack physiological mechanisms to generate heat.

5. **Considering Homeothermic Animals:**
- **Homeothermic Animals:** These are warm-blooded animals that can maintain a constant body temperature regardless of external conditions. They generate heat through metabolic processes and are not severely affected by temperature changes.

6. **Conclusion:**
Based on the analysis, the type of animals that are severely affected by changes in environmental temperature are **poikilothermic (cold-blooded) animals**.

**Final Answer: Poikilothermic (cold-blooded) animals.**

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