The process by which organisms keep their internal condition relatively stable is called

Step 1: Analyze the question The question asks for the name of the process that keeps an organism's internal conditions (temperature, water level, blood sugar, pH and so on) relatively constant, even when the external environment changes.

Step 2: Explain the concept Homeostasis comes from two Greek words: homeo (similar or the same) and stasis (standing or staying). Together they mean "staying the same". Examples include:

• Temperature regulation: sweating when hot and shivering when cold.
• Blood sugar control: insulin lowers blood sugar and glucagon raises it.
• Osmoregulation: the kidneys control the water and salt balance of the body.

Step 3: Check each option

• A. Metabolism: the sum of all chemical reactions in the body (anabolism and catabolism). It is not about keeping conditions stable.
• B. Evolution: gradual change in species over many generations. It has nothing to do with day-to-day internal balance.
• C. Gametogenesis: the formation of gametes (sperm and egg cells) in reproduction.
• D. Homeostasis: the maintenance of a stable internal environment. This matches the question.

Step 4: Answer The correct answer is D. homeostasis.

Exam tip: Link the word parts: homeo = same, stasis = standing still. If a question says "stable internal environment", "constant conditions" or "balance", think homeostasis straight away.