Cellular function refers to the various processes that occur within a cell to maintain life. These processes include energy production, nutrient absorption, waste removal, and communication with other cells. Each cell has specialized structures called organelles, such as mitochondria for energy and ribosomes for protein synthesis, that help carry out these functions. Cells also respond to their environment through signaling pathways, allowing them to adapt to changes. For example, when a cell detects a lack of nutrients, it may alter its metabolism to conserve energy. Overall, cellular function is essential for growth, repair, and overall health in living organisms.