Mitochondria are one of a kind organelle present in the cells. Rightly, called the powerstation of the cells which burns the food we eat with oxygen which we breath to form water. Every heart beat, every word we speak, every body movement is powered by mitochondria. It been proved that mitochondria was once a simple cell by itself. One simple cell was eaten by another simple cell which leads further to a complex life. The multicellularity requires vast amount of energy and this was provided by mitochondria.
Research has shown due to this function of mitochondria, it’s involved in range of cell functions. Even though they are just complex machinery to make ATP, they contain their own circular DNA mtDNA and array of proteins. Mitochondria is a system in itself, lt can sustain itself forming thousands of copies 10 17 in the cytoplasm of the cell.
It has double membrane structure and energy is mostly generated from hydrocarbons i.e. sugars and acids. Pyruvate goes into the mitochondria and it is burned in the cycle called Tricarboxylic Acid cycle (TCA). TCAs only job is to strip hydrogens from hydrocarbon, which it puts on carrier NAD forming NADH2. Then this NADH2 is burned through electron transport chain, where it reduces an atom of oxygen to molecule of water. This is where respiration comes into picture leading to Aerobic Respiration.
Each of the mitochondria acts as a capacitor which positively charged outside the inner membrane and negatively charged inside. So we have approximately 10 17 charged capacitors due to hydrogen ion gradient present across the inner membrane. And this gradient is used to produce energy rich ATP. Then these energy packets are distributed throughout the cell for its efficient functioning.
But not all the powerhouses are efficient. Some of them start producing less power and more heat. Basically in our body we use food for two purposes: for energy and to maintain the body temperature. How our mitochondria do it, is by using few proton gradients it bypasses ATP synthatase and it short circuits the capacitor. It burns more hydrogen instead of forming ATP. This balancing between heat and ATP production is called coupling efficiency.
Other important side products in mitochondria are the oxygen radical like superoxides and hydroxyl radicals. These radicals induce mutational breaks in DNA. Thus they are damaging to the mitochondria leading to less energy generation and cells tend to malfunction. This triggers the body function to get rid of such cell by apoptosis, which an orchestrated mechanism involving mitochondrial membrane integrity. It’s been observed that each individual are born with certain number of mitochondria in the cell enough till the age of around fifty. Then the downhill starts, as not all cells can sustain so much oxidative damage.
This downhill leads to various age related diseases, neurodegenerative diseases, diabetes, heart diseases, cancer etc. Thus, certainly research on molecular and physiological aspect of mitochondria function would take us near to understanding of aging and all the related diseases.
Research has shown due to this function of mitochondria, it’s involved in range of cell functions. Even though they are just complex machinery to make ATP, they contain their own circular DNA mtDNA and array of proteins. Mitochondria is a system in itself, lt can sustain itself forming thousands of copies 10 17 in the cytoplasm of the cell.
It has double membrane structure and energy is mostly generated from hydrocarbons i.e. sugars and acids. Pyruvate goes into the mitochondria and it is burned in the cycle called Tricarboxylic Acid cycle (TCA). TCAs only job is to strip hydrogens from hydrocarbon, which it puts on carrier NAD forming NADH2. Then this NADH2 is burned through electron transport chain, where it reduces an atom of oxygen to molecule of water. This is where respiration comes into picture leading to Aerobic Respiration.
Each of the mitochondria acts as a capacitor which positively charged outside the inner membrane and negatively charged inside. So we have approximately 10 17 charged capacitors due to hydrogen ion gradient present across the inner membrane. And this gradient is used to produce energy rich ATP. Then these energy packets are distributed throughout the cell for its efficient functioning.
But not all the powerhouses are efficient. Some of them start producing less power and more heat. Basically in our body we use food for two purposes: for energy and to maintain the body temperature. How our mitochondria do it, is by using few proton gradients it bypasses ATP synthatase and it short circuits the capacitor. It burns more hydrogen instead of forming ATP. This balancing between heat and ATP production is called coupling efficiency.
Other important side products in mitochondria are the oxygen radical like superoxides and hydroxyl radicals. These radicals induce mutational breaks in DNA. Thus they are damaging to the mitochondria leading to less energy generation and cells tend to malfunction. This triggers the body function to get rid of such cell by apoptosis, which an orchestrated mechanism involving mitochondrial membrane integrity. It’s been observed that each individual are born with certain number of mitochondria in the cell enough till the age of around fifty. Then the downhill starts, as not all cells can sustain so much oxidative damage.
This downhill leads to various age related diseases, neurodegenerative diseases, diabetes, heart diseases, cancer etc. Thus, certainly research on molecular and physiological aspect of mitochondria function would take us near to understanding of aging and all the related diseases.
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