Sunday, November 28, 2010

Mitochondria (What Makes the Individual)

My Human body is exceedingly complex. It is composed of countless parts, organs, organs systems, tissue, cells, and chemical reactions that function in a vary delicate harmony. At any time One of these things could get out of sync and then I would cease to function. This death inevitably will happen. At the root of all this metabolic activity one miniscule and most basic part of the human body makes it all possible. A tiny organelle called mitochondria that exists in every cell.

Mitochondria are extremely vital to the existence of human beings, because they are the powerhouse. The use of energy to power our body is made possible by them. Inside the mitochondria an organelle called the matrix transforms ADP into ATP, or adenosine triphosphate. All cells use ATP to carry out the functions of life.

There is one vary strange thing about mitochondria which sets it apart from the rest of the body. It has it's own DNA. It's entirely different from the coiling chromosomes of most human DNA in the nucleus of the cell. Mitochondrian DNA exists in a plasmid, or loop like form that is similar to the way bacteria sequester their DNA. This DNA is passed down only from the mother during reproduction. Mitochondria goes through vary little recombination, or change, because of this. It's DNA can be used to trace the linage of an individual back thousands of years, because it remains virtually the same during that long duration of time. One has to wonder why mitochondria is so different from every other organelle. One scientist believed he had the answer. Paul Portier published his book Les Symbiotes in 1918 with a highly controversial statement it. Portier said “All beings, apart from bacteria, are double being formed by the association of two different kinds of creatures”. He was in fact referring to mitochondria. Portier's theory was that mitochondria where a type of bacteria that live inside the cell, produce energy for the cell and are passed down genetically during conception of a human being. To test his theory Portier devised an experiment to see if mitochondria could be cultivated outside of the cell. He was successful in cultivating mitochondria from certain plants and invertebrates. In 1918, when Portier published his findings his theory came under much scrutiny and was dismissed by the scientific community. In modern times Portier's conclusion is now regarded as a scientific truth.

This conclusion makes quite allot of previously held notions confusing. Mitocondrian are definitely a vital organelle that the human body needs to sustain itself, but it is also it's own species septet form us, and yet the human species encompasses it. The mitocondrian genome is still part of the human genome. With this knowledge I can only wonder; what makes me human? What makes me an individual if I am made up by not just multiple cells, but multiple species all functioning to make one conscience that is self aware? Can each mitocondrian be regarded as an individual? Can each cell be regarded as an individual when they in fact can exist and grow outside the human body. This is not even to mention the wealth of microorganisms that live inside the human body. Some are harmful, some are beneficial, and others are vital. Are they me as well? When I tap someone on the shoulder in the dark with my hand I may say “It's me” to clarify. Chop off my hand and that it is not me. It is only a part of me that has been removed. If any vital part of my body is taken away from me and I cease to exist, because I am dead, then am I still Helen, or am I a part of Helen that only exists as a whole? What if mitochondrian where that vital part taken away that no longer makes me, me? Some may consider this thought belittling, and others may find it depressing, but I find it inspiring. It blows my mind to say the least. All the neurons living inside my head, each capable of living outside me on their own, work in perfect unison to fire a change of electrons that all compose one thought: I am Helen. Take a number of the neurons away and I am no longer able to form the thought. I can't think, therefore I am not. In my mind I am no longer Helen without my cells, I am no longer Helen without my bacteria, and I am no longer Helen without my mitochondria.

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