What is the function of mitochondrion in a cell?

The mitochondrion is often referred to as the "powerhouse of the cell" because its primary function is energy production. It is the site where cellular respiration occurs, a process that converts biochemical energy from nutrients into adenosine triphosphate (ATP), which cells utilize as a source of energy for various functions. Mitochondria are equipped with their own DNA and machinery to produce ATP efficiently through aerobic respiration, particularly by processing glucose and oxygen.

In contrast to energy production, photosynthesis is an exclusive function of chloroplasts found in plant cells, while protein synthesis occurs primarily in ribosomes, and cell division involves structures like the spindle apparatus and centrioles. Thus, the role of the mitochondrion in energy production is fundamental to the survival and functioning of both plant and animal cells.