Final answer:
Homeostasis is the ability of an organism to maintain a stable internal environment despite external changes, and it is an essential characteristic of all living things. It involves dynamic homeostatic processes and feedback mechanisms to ensure internal equilibrium, crucial for survival.
Step-by-step explanation:
If an animal allows its internal and external conditions to be equal, it is said to show homeostasis. Homeostasis is the ability to maintain a stable internal environment despite changes in external conditions. This is a fundamental concept in biology, showing that all living things manage to keep their internal environment relatively constant. For example, humans maintain a stable body temperature, birds fluff their feathers to retain warmth, and lizards bask on warm rocks to raise their body temperature.
Homeostatic processes are dynamic, meaning they are continuously adjusting to maintain equilibrium in the body's systems, regardless of external changes, such as temperature fluctuations or variations in the levels of certain substances in the blood, like glucose or calcium.
Organisms use various feedback mechanisms to maintain their internal environments and to respond adequately to environmental changes. These homeostatic mechanisms reflect both common ancestry and evolution through adaptation in different environments, which is pivotal for survival across a wide range of conditions.