Why is mitochondria needed

Mitochondria are similar to plant chloroplasts in that both organelles are able to produce energy and metabolites that are required by the host cell.

As discussed above, mitochondria are the sites of respiration, and generate chemical energy in the form of ATP by metabolizing sugars, fats, and other chemical fuels with the assistance of molecular oxygen. Chloroplasts, in contrast, are found only in plants and algae, and are the primary sites of photosynthesis.

These organelles work in a different manner to convert energy from the sun into the biosynthesis of required organic nutrients using carbon dioxide and water. Like mitochondria, chloroplasts also contain their own DNA and are able to grow and reproduce independently within the cell.

In most animal species, mitochondria appear to be primarily inherited through the maternal lineage, though some recent evidence suggests that in rare instances mitochondria may also be inherited via a paternal route. Typically, a sperm carries mitochondria in its tail as an energy source for its long journey to the egg. When the sperm attaches to the egg during fertilization, the tail falls off. Consequently, the only mitochondria the new organism usually gets are from the egg its mother provided.

Therefore, unlike nuclear DNA, mitochondrial DNA doesn't get shuffled every generation, so it is presumed to change at a slower rate, which is useful for the study of human evolution. Mitochondrial DNA is also used in forensic science as a tool for identifying corpses or body parts, and has been implicated in a number of genetic diseases, such as Alzheimer's disease and diabetes. License Info. Image Use. Custom Photos.

Site Info. Contact Us. A current challenge in — and goal of — mitochondria research is pinpointing exactly how alterations in mitochondrial machinery lead to disease. Achieving this involves mapping the many interactions among the proteins involved in mitochondrial function. So far, scientists have identified nearly all of the organelle's roughly 1, proteins and learned what about half of them do. This work, says Mootha, ultimately could transform the burgeoning area of mitochondrial medicine by offering new clues for developing therapies that restore or even enhance the organelle's performance.

Inside the Cell Booklet. Mitochondria: determinators Recent research indicates that in addition to converting energy mitochondria play quite a large part in determining when a cell will die by ordinary cell death necrosis or programmed cell death apoptosis. In apoptosis the mitochondrion releases a chemical, cytochrome c, and this can trigger programmed cell death apoptosis. Mitochondria are also thought to influence, by exercising a veto, which eggs in a woman should be released during ovulation and which should be destroyed by programmed cell death apoptosis.

This is part of a process called atresia. It appears that in this process mitochondria and the nucleus of the cell in which the mitochondria reside, are screened for biochemical compatibility.

The pairs that are incompatible are shut down by programmed cell death. Mitochondria: generators of disorders and disease Mitochondria are very important energy converters. In this process they produce waste products. In mitochondria these are called reactive oxygen species ROSs. These mutations are the source of mitochondrial disease that can affect areas of high energy demand such as brain, muscles, central nervous system and the eye.

Mutations caused by ROSs have been suggested as contributing to the ageing process. Many more mutations in mitochondrial DNA take place in people over 65 than in younger people, but many more factors are involved in this inevitable at present but variable process.

The working of mitochondria at a molecular level is also involved in the good or otherwise progress of people in the very early stages of recovery following open heart and transplant surgery. It appears that the drugs damage mitochondria and block the production of mitochondrial DNA. French and Japanese centenarians appear to have advantageous mutations in their mitochondrial DNA.

This is interesting but since we do not know about cause and effect, care needs to be exercised when considering these figures. In the field of sport it is not difficult to reason that athletes with high counts of mitochondria in their heart and other appropriate muscle cells are able to do just that little bit better than others less well endowed.

Those membranes function in the purpose of mitochondria, which is essentially to produce energy. That energy is produced by having chemicals within the cell go through pathways, in other words, be converted. And the process of that conversion produces energy in the form of ATP, because the phosphate is a high-energy bond and provides energy for other reactions within the cell.

So the mitochondria's purpose is to produce that energy.