What is homeostasis?

What is homeostasis?

• A. Maintaining a constant external environment
• B. Keeping a constant internal environment
• C. Regulating heartbeat
• D. Controlling sleep

Answer: (B)

Maintaining a stable internal environment is what homeostasis means. The body works to keep conditions inside the body—like core temperature, pH, and glucose levels—within narrow limits even when the outside environment changes. This balance is achieved mainly through negative feedback: sensors detect deviations, a control system processes the information, and effectors produce responses that bring things back to normal. For example, if the body gets too hot, sweating and increased blood flow to the skin help cool it down; if it gets too cold, shivering and conserving heat help raise the temperature. While activities such as regulating heartbeat or controlling sleep are part of how the body maintains stability, homeostasis specifically refers to keeping the internal environment constant rather than the external surroundings.

Maintaining a stable internal environment is what homeostasis means. The body works to keep conditions inside the body—like core temperature, pH, and glucose levels—within narrow limits even when the outside environment changes. This balance is achieved mainly through negative feedback: sensors detect deviations, a control system processes the information, and effectors produce responses that bring things back to normal. For example, if the body gets too hot, sweating and increased blood flow to the skin help cool it down; if it gets too cold, shivering and conserving heat help raise the temperature. While activities such as regulating heartbeat or controlling sleep are part of how the body maintains stability, homeostasis specifically refers to keeping the internal environment constant rather than the external surroundings.