The animals that rely on the heat from environment than metabolism to raise their body temperature are, in strict sense, called

Options

A. ectothermic
B. poikilothermic
C. homeothermic
D. endothermic

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about animals that depend on environmental heat rather than their metabolic processes to regulate their body temperature.

2. **Identifying Key Terms**: The key terms in the question are "heat from environment," "metabolism," and "body temperature." This indicates that we are looking for a specific classification of animals based on their thermoregulation strategy.

3. **Defining Ectothermic Animals**: Ectothermic animals, also known as cold-blooded animals, are those that cannot internally regulate their body temperature. Instead, they rely on external environmental conditions to maintain their body heat.

4. **Contrasting with Other Terms**:
- **Endothermic Animals**: These animals, often referred to as warm-blooded, can regulate their body temperature through metabolic processes, maintaining a constant internal temperature regardless of the environment.
- **Poikilothermic Animals**: This term refers to animals whose body temperature fluctuates with the temperature of the environment, which is a characteristic of ectothermic animals.

5. **Conclusion**: Based on the definitions and characteristics discussed, the correct answer to the question is "ectothermic."

**Final Answer**: The animals that rely on heat from the environment rather than metabolism to raise their body temperature are, in strict sense, called **ectothermic** animals.

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