OCR General Certificate of Secondary Education (GCSE) Biology Practice Exam

Which of the following is true regarding homeostasis?

1. It only applies to temperature regulation

2. It involves maintaining internal stability

3. It is irrelevant to glucose levels

4. It only occurs during physical activity

The correct answer is: It involves maintaining internal stability

Homeostasis is the process through which living organisms maintain a stable internal environment despite changes in external conditions. This stability is crucial for the proper functioning of cells and overall health. The correct answer highlights that homeostasis involves maintaining internal stability, which encompasses various physiological parameters, including temperature, pH, hydration, and the concentrations of ions and nutrients, such as glucose. The concept of homeostasis is not limited to a single aspect; it plays a vital role across multiple systems within the body. For instance, while body temperature regulation is an important component, homeostasis also includes regulating blood sugar levels, blood pressure, and fluid balance. This comprehensive regulation allows organisms to adapt to different environments and stresses, ensuring their survival. In contrast, the other statements suggest limited or incorrect interpretations of homeostasis, such as restricting it to specific activities or parameters, which do not capture the broad and essential nature of this biological process.