Biology and pathology of the mitochondrion.

The mitochondrion is a highly efficient organelle that is essential for the function of cells. It is currently accepted that mitochondria originated from primitive nonphotosynthetic bacteria that were engulfed by early eucharyotic cells. Most of the normal and pathologic interactions between mitochondria and the cells that contain them can be viewed as symbiotic processes. The main features of mitochondrial structure and function and some of the pathological disorders that involve this organelle are reviewed.