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Molecular Basis of Heredity: Part 2. Genomes

Author(s): Raye L. Alford, PhD


Mitochondria are the power plants of cells: they provide cells with the chemical energy needed to perform the metabolic tasks associated with life. It is widely believed that mitochondria are the remnants of ancient energy-producing symbiotic bacterial cells that were assimilated into eukaryotic cells. Similarly, chloroplasts in green plants are believed to be remnants of photosynthetic bacteria.

The mitochondrial chromosome encodes 13 proteins, 2 rRNAs and 22 tRNAs. Mitochondria obtain many of their proteins from genes encoded in the nuclear genomes of cells. Nuclear encoded proteins are imported into the mitochondria after translation.