Which term refers to maintaining internal stability?

Which term refers to maintaining internal stability?

• A. Homeostasis
• B. Metabolism
• C. Respiration
• D. Digestion

Answer: (A)

Maintaining internal stability is homeostasis. Organisms use feedback mechanisms to keep internal conditions like temperature, pH, fluid balance, and energy levels within narrow limits despite changes in the outside environment. When a variable drifts from its set point, sensors detect the change and effectors respond to bring it back toward normal. For example, overheating triggers sweating and increased blood flow to cool the body, while cooling triggers shivering and reduced blood flow to generate and conserve heat. Hormonal systems, such as insulin and glucagon regulating blood glucose, also help keep internal conditions steady. Other terms describe processes that support life but don’t capture the regulation of internal stability alone. Metabolism covers all chemical reactions in the body; respiration is about energy production and gas exchange at the cellular level; digestion is the breakdown of food. Homeostasis specifically refers to keeping the body's internal environment stable.

Maintaining internal stability is homeostasis. Organisms use feedback mechanisms to keep internal conditions like temperature, pH, fluid balance, and energy levels within narrow limits despite changes in the outside environment. When a variable drifts from its set point, sensors detect the change and effectors respond to bring it back toward normal. For example, overheating triggers sweating and increased blood flow to cool the body, while cooling triggers shivering and reduced blood flow to generate and conserve heat. Hormonal systems, such as insulin and glucagon regulating blood glucose, also help keep internal conditions steady.

Other terms describe processes that support life but don’t capture the regulation of internal stability alone. Metabolism covers all chemical reactions in the body; respiration is about energy production and gas exchange at the cellular level; digestion is the breakdown of food. Homeostasis specifically refers to keeping the body's internal environment stable.