Introduction
In our body the muscles lury has multitude structure that is known as mitochondria. Mitochondria multiply itself several times as much like bacterial cells. When they get too large, they undergo fission. This involves a furrowing of the inner and then the outer membrane as if someone was pinching the mitochondria. Then the two daughter mitochondria split. Of course, the mitochondria must first multiply itself several times as their DNA. The size range is from 1 to 10 micrometers (ÎĽm).
Mitochondria is said “ power house”because of their energy generation for cells. This energy is called ATP (adenosine triphosphatw) which is used as a source of chemical energy. Mitochondria perform some other process like
- Cell signaling
- Cellular differantiation
- Apoptosis
- Controll of cell cycle
- Cell growth
The number of Mitochondria in a cell varies widely by organisms and tissue type. Many cells have single Mitochondria while some cells have thousands of them. In a man , Mitochondria may have around 615 distinct proteins depending on the tissue of origin. Cell nucleus mainly contained with the DNA cell. Finally, mitochondria have been implicated in several human diseases and may play a role in being older.
Function
Mitochondria convert organic materials into cellular energy in the form of ATP. Mitochondria gives an important appearance in many metabolic tasks. Which are as follows:
- Regulation of the membrane potential.
- Apoptosis-programmed cell death.
- Glutamate-mediated excitotoxic neuronal injury.
- Cellular proliferation.
- Regulation of the cellular redox state.
- Heme synthesis.
- Steroid synthesis.
Some of the function of the mitochondria is done in only special types of cells.. For example, mitochondria in liver cells contain enzymes that allow them to detoxify amonia, a waste product of protien metabolism. A mutation in the genes regulating any of these functions can result in mitochondrial disease.
How we got mitochondria and what they were (about their own DNA)
Mitochondria contain their own DNA ,ribosom’s and can produce many of their own protiens. The DNA is circular and lies in the matrix. In punctuate structures called “nucleoids”. Each nucleoid has 4 or 5 copies of Mitochondrial DNA. In some cells and situation, it is normal to have areas with many mitochondria. If Mitochondria could not undergo fission it would continue to grow and grow and eventually become a huge organelle. The replication and production of cristae in response to defective mitochondria and low ATP will be as if ATP is low, the cell is stimulated to make more mitochondria. But, if they are defective as in the lower photograph, ATP cannot be produced.
The food we eat is oxidized to produce high-energy electrons that are converted to stored energy. This energy is stored in high energy phosphate bonds in a molecule called adenosine triphosphate, or ATP. ATP is converted from adenosine diphosphate by adding the phosphate group with the high-energy bond. Various reactions in the cell can either use energy (whereby the ATP is converted back to ADP, releasing the high energy bond) or produce it (whereby the ATP is produced from ADP.
Importance of mitochondria
The significance of the working of the mitochondria is to get as much ATP out of glucose as possible. If we do not inhale oxygen ,we get only 4 molecules of ATP energy packets for each glucose molecule. However, if we have oxygen, then we get to run the Kreb’s cycle to produce many more hydrogen ions that can run those ATP pumps. From the Kreb’s cycle we get 24-28 ATP molecules out of one molecule of glucose converted to pyruvate (plus the 4 molecules we got out of glycolysis). So, you can see how much more energy we can get out of a molecule of glucose if our mitochondria are working and if we have oxygen.
Works cited
Henze K, Martin W (2003). “Evolutionary biology: essence of mitochondria”. Nature 426 (6963): 127-8.
Herrmann JM, Neupert W (2000). “Protein transport into mitochondria”. Curr Op Micro. 3 (2): 210-214.
McBride HM, Neuspiel M, Wasiak S (2006). “Mitochondria: more than just a powerhouse”. Curr. Biol. 16 (14): R551–60. PMID 16860735.