What is the function of mitochondria?

Mitochondria are often referred to as the "powerhouses" of the cell because their main function is to produce energy. They do this through a process called cellular respiration, where they convert nutrients, primarily glucose, into adenosine triphosphate (ATP), the main energy currency of the cell. During this process, the mitochondria use oxygen to break down the glucose molecules, releasing energy that the cell can utilize for various activities, such as growth, repair, and movement.

This ability to generate energy is crucial for the survival and functioning of both single-celled and multicellular organisms. Other options mention different cellular functions: photosynthesis occurs in chloroplasts in plant cells, protein synthesis takes place in ribosomes, and support and structure are primarily provided by the cell membrane and cell wall. Each of these processes is vital in their own right, but they do not represent the primary role of mitochondria.