Each organism has some degree of homeostasis, i.e., it is able to make adjustments so that its internal environment remains relatively constant despite changes in the external environment.

Answer

### Step-by-Step Solution:

1. **Understanding Homeostasis**:
- Homeostasis refers to the ability of an organism to maintain a stable internal environment despite external changes. This is crucial for sustaining life.

2. **Dynamic Process**:
- Homeostasis is not a static condition; it is a dynamic process. Organisms continuously adjust their internal systems to respond to fluctuations in their external environment.

3. **Role of the Endocrine and Nervous Systems**:
- In humans, the endocrine system (hormonal responses) and the nervous system (neural responses) play vital roles in detecting changes in both internal and external environments. They act as sensors and regulators.

4. **Feedback Mechanisms**:
- Organ systems utilize feedback mechanisms to maintain homeostasis. These mechanisms can be negative (counteracting changes) or positive (enhancing changes) to stabilize the internal environment.

5. **Examples of Homeostasis**:
- Examples include temperature regulation (sweating or shivering), blood sugar levels (insulin and glucagon), and fluid balance (thirst response).