What Is Mitochondria?

Mitochondria are filamentous organelles of all aerobic cells of higher animals and plants and also certain microorganism like protozoa. Studies show that that mitochondria are the direct descendants of a bacterial endosymbiont that became established at an early stage in a nucleus-containing host cell (Gray et al., 1999). Mitochondria are surrounded by a double-membrane system, consisting of inner and outer mitochondrial membranes separated by an intermembrane space. (Cooper, 2000). It has the outer membrane and the inner membrane. The membranes are made up of phospholipids and proteins. The mitochondria has an outer membrane which is smooth and composed of equal amounts of phospholipids and proteins. It has a large number of special proteins known as the porins. The porins are integral membrane proteins and they allow the movement of molecules that are of 5000 daltons or less in weight to pass through it. The outer membrane is freely permeable to nutrient …show more content…
This folding help to increase the surface area inside the organelle. The cristae and the proteins of the inner membrane aids in the production of ATP molecules (Cooper, 2000). There are various chemical reactions taking place in the inner membrane of the mitochondria. Unlike the outer membrane, the inner membrane is strictly permeable, it is permeable only to oxygen, ATP and it also helps in regulating transfer of metabolites across the membrane. There is a space between the outer and inner membrane of the mitochondria, which has the same composition as that of the cell's cytoplasm; there is a difference in the protein content in the intermembrane space (Cooper, 2000). The matrix of the mitochondria is a complex mixture of proteins and enzymes. These enzymes are important for the synthesis of ATP molecules, mitochondrial ribosomes, tRNAs and mitochondrial