Biological functions refer to the processes that occur within living organisms to maintain life. These functions include essential activities such as metabolism, which involves converting food into energy, and reproduction, the process by which organisms produce offspring. Other important functions include growth, response to stimuli, and homeostasis, which is the ability to maintain a stable internal environment. Each biological function is crucial for the survival and health of an organism. For example, respiration allows cells to obtain energy from nutrients, while circulation helps transport oxygen and nutrients throughout the body. Together, these functions enable organisms to adapt, thrive, and interact with their environment.