What are Mitochondria?
In cell biology, a mitochondrion (plural mitochondria) is a membrane-enclosed organelle found in most eukaryotic cells.These organelles range from 1–10 micrometers (μm) in size. Mitochondria are sometimes described as “cellular power plants” because they generate most of the cell’s supply of adenosine triphosphate (ATP), used as a source of chemical energy. In addition to supplying cellular energy, mitochondria are involved in a range of other processes, such as signaling, cellular differentiation, cell death, as well as the control of the cell cycle and cell growth.The word mitochondrion comes from the Greek μίτος or mitos, thread + χονδρίον or khondrion, granule. Their ancestry is not fully understood, but, according to the endosymbiotic theory, mitochondria are descended from ancient bacteria, which were engulfed by the ancestors of eukaryotic cells more than a billion years ago. Several characteristics make mitochondria unique.
Mitochondria are membrane enclosed organelles found in most eukaryotic cells. They generate most of the cell’s supply of ATP which is used as a source of energy. Mitochondria have their own independent genome, the material of which is known as mitochondrial DNA (mtDNA). Mitochondria contain inner and outer membranes, forming 5 distinct compartments: outermembrane, intermembrane space, inner membrane, cristae space (formed by invaginations of the inner membrane), and the matrix (space within the inner membrane). Much of the activity of the mitochondria occurs within the inner mitochondrial membrane (IMM).
Is that where we get our energy? Q: Are mitochondria present in all plants and animals? What is the current theory on how mitochondria evolved? Are they all the same? Someone, Texas, USA A: “Biology Department, UNM” a young woman answers the phone. I ask to speak with an expert on mitochondria (my-toe-KON-dree-a). She pauses. “What’s mitochondria?” I hear her say to a friend. Mitochondria are tiny sacs—so small you need an electron microscope to see them—elongated, like a sausage. Many bop around in each heart, pancreas, or kidney cell. Few live in a skin cell. All living cells, however, have mitochondria (except bacteria and cyanobacteria, formerly called blue-green algae). Mitochondria power life. Their job is to burn food and produce power packets (called ATP molecules, whose initials stand for Adenosine Tri Phosphate). The young woman comes back on the phone and refers me to Don Natvig, a molecular biologist and professor at the University of New Mexico. Unfortunately, he’s in a te
