Why are most systems in the human body regulated by negative feedback mechanisms?

• A. Because negative feedback systems are less energy-efficient than positive feedback systems.
• B. Because negative feedback helps maintain homeostasis by counteracting deviations from a set point.
• C. Because negative feedback amplifies changes, allowing rapid adaptation to new conditions.
• D. Because negative feedback only operates during periods of disease or stress.

Answer: (B)

Verified step by step guidance

1. Understand the concept of homeostasis: Homeostasis refers to the body's ability to maintain a stable internal environment despite external changes. This stability is crucial for proper functioning of cells and organs.
2. Learn about negative feedback mechanisms: Negative feedback is a regulatory process where a change in a system triggers a response that counteracts or reduces the initial change, bringing the system back to its set point or equilibrium.
3. Compare negative feedback to positive feedback: Negative feedback works to stabilize systems by reducing deviations, while positive feedback amplifies changes and is typically used in processes like childbirth or blood clotting, which require rapid responses.
4. Identify the role of negative feedback in maintaining homeostasis: Negative feedback mechanisms are energy-efficient and prevent extreme fluctuations in physiological parameters, such as body temperature, blood glucose levels, and pH, ensuring the body remains within a functional range.
5. Evaluate the incorrect options: Negative feedback does not amplify changes, operate only during disease or stress, or require more energy than positive feedback. Its primary role is to maintain homeostasis by counteracting deviations from a set point.