Organisms that can maintain a constant internal temperature are called as

Options

A. homoiothermic
B. poikilothermic
C. oilgothermic
D. heterothermic

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the term used to describe organisms that can maintain a constant internal temperature despite changes in their external environment.

2. **Identifying Key Terms**: The key terms in the question are "constant internal temperature" and "organisms". This indicates that we are looking for a specific classification of organisms based on their ability to regulate body temperature.

3. **Exploring Organism Categories**: Organisms can be broadly categorized based on their temperature regulation:
- **Homeothermic (Endothermic)**: These organisms can maintain a stable internal body temperature regardless of external conditions. They are often referred to as warm-blooded animals.
- **Poikilothermic (Ectothermic)**: These organisms cannot regulate their body temperature and their internal temperature fluctuates with the ambient temperature. They are often referred to as cold-blooded animals.

4. **Examples of Homeothermic Organisms**: Birds and mammals are the primary examples of homeothermic or endothermic organisms. They possess physiological mechanisms to maintain their body temperature.

5. **Conclusion**: Based on the definitions and examples provided, the correct term for organisms that can maintain a constant internal temperature is **Homeothermic** (or Endothermic).

**Final Answer**: Organisms that can maintain a constant internal temperature are called **Homeothermic** (or Endothermic).

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