important points on mitochondria
Answers
1. Cellular respiration: It is a well-known fact that mitochondria are responsible for cellular respiration. The oxygen from lungs is transferred by blood to the cells. In the cells, this oxygen is utilized by mitochondria and then carbon dioxide is released. This carbon dioxide is again carried back to the lungs for expulsion from the body.
cellular energyCell requires energy for many purposes like DNA, RNA, protein synthesis, cell division etc. Most of the processes occur due to bond formations or with the involvement of enzymes and phosphate. These enzymes and phosphorylations are energy dependent. The required energy is supplied by mitochondria to the cell.
2. Cellular energy production: Mitochondria produce the energy as ATP (adenosine triphosphate) by oxidative phosphorylation. This comes from the breakdown of carbohydrate substrates in the presence of oxygen.
Once we consume food, it is digested and absorbed into the blood as glucose. This is supplied to each and every cell and organ in the body. The glucose is then broken down to release the energy. This is how the food in the body is converted to energy.
3. Calcium homeostasis: Mitochondria is involved in calcium homeostasis inside the cell. Calcium is taken into the cell from outside through the cell membrane. This calcium is stored in calcium vesicles inside the cell. But when required, calcium is released and again stored in the vesicles.
mitochondria function calcium homeostasis
Mitochondria with large amounts of calcium and reactive oxidative radicals.
However, mitochondria also take up calcium and also release it back into cytoplasm. Read for more on mitochondria and calcium
4. Promote cell cell growth and multiplication: Mitochondria are required for cell growth and multiplication. They form a network of tubules to enhance protein synthesis. Specifically a protein called cyclin is formed which acts as a check point protein. Its role is to ensure the cell to undergo division at right time when all the aspects are ready for the process.
5. Role in cell death: Mitochondria are also responsible for programmed cell death. This is called as apoptotic cell death. It occurs mostly in conditions of injury or irreversible damage to the cell. The membrane of mitochondria releases caspases which are apoptosis factors.
mitochondrial function cell death
Mitochondria during injury can leak apoptotic proteins which activate cell death mechanism.
Further, disruption of mitochondria function can lead to sudden stoppage of energy supply leading to shock and immediate death.
6. Generate oxidative radicals: They also generate oxidative radicals during energy formation. These oxidative radicals are necessary for various other reactions. But the main contribution of these oxidative radicals is in ageing.
7. Support nerve conduction: Mitochondria support nerve conduction by helping neurotransmitter release.
mitochondria function-neurotransmitter release
Mitochondria help in release of neurotransmitters at the nerve ending for nerve conduction. (Ca++ = calcium)
Hence, there are more number of mitochondria near the nerve endings, especially at the synapse. These mitochondria produce sufficient energy in the form of APT. Further, they also release calcium into the cytoplasm for the release of neurotransmitters at the nerve junctions.
8. Organs of metabolism: These are the cell organelles where the citric acid cycle or TCA cycle (tricarboxylic acid cycle) and other respiratory cycles of the cell take place.
9. Synthesize bio-molecules: Many bi-products like glutarate, glyco-oxalic acid are produced during the TCA cycle chemical reactions. These bi-products are further utilized by the cell. They form glutamine, glycine like amino acids which are essential for normal physiology.
10. Contribute to diseases: Abnormalities in mitochondria can lead to many diseases like mood disorders, neurodegeneration, cardiac problems, cancer etc.
Answer:
Explanation:
ther is presence of matrix which increases the surface area