The appearance of the first cells
Cells, source image of pixabay
Seems to be that the origin of the life was a slow and staggered process of chemical evolution from inorganic simple substances, which happened of natural form during the formation and development of the primitive ground.
With this theory many positions are born philosophical on this case, as what the Greek classic thinkers argued, who was already wondering which could have been the origin of what is known by life, and several restored to saying gave questions does not exempt from imagination and fantasy. For many years, one believed that the life could originate from form spontaneous in any moments.
With the time of realizaron an aseries of experiment to try to understand this theory, as pooh the case of Louis Pasteur, in the year 1862, the impossibility of a spontaneous origin of the life, at present, we know that the age of the ground is approximately 48.000 to 50.000 million years and that the alive organisms appeared 4.000 million years, thanks to different investigations, one affirms that in epoch early in the ground many inorganic compounds perished, which they were different from the superficial water of the ocean, this one they provided a culture medium in which, of someone it forms, the first alive cell appeared.
In the ambience of the primitive ground, the theory most accepted on the composition of primitive ambience is the one that it supports, that it was not containing oxygen and was rich in hydrogen, methane, ammonia and water, also suggestion does, where the organic compounds appeared from inorganic components as the ammonia, the methane and water steam, that were present in the ambience and geoferas, where these gases could be activated by the radiant energy of the solar light or for discharging electrical and reacted between if giving to place to such organic simple compounds as the amino acid and you sweeten.
The biological evolution began when the cells formed. The following critical step as you go basis of the life, it was the inclusion of the biological complex molecules inside membranes, which kept them together and increased his frequency of interaction. The molecules of lípidos constituted the critical component because these molecules are not solubres in waters and lead to membranes in the shape of movies or plates.
These movies it tends to form vesicles spheroids, which can contain encapsulated in his certain interior sets of biological molecules. The scientists postulate that they do 3.800 million years, this natural process of membrane formation led to the first capable cells of autorreplicación, an event that marked the beginning of the biological evolution.
Life / Life: The science of the biology / The Science of Biology - Page 11; for David Sadava, William H. Purves - 2009.
The appearance of the first cell, inside this context he manages, that the organic compounds, which formed firstly péptidos, polinuclótidos, polisacáridos and lípidos. From this organic broth the first alive cells formed. These cells would be heterótrofas and anaerobic, since in the primitive ambience there was no oxygen, in such a way that there would be used the organic molecules of the ocean as source of energy and matter to form his structures.
Stanley Miller,source of image of mastery of wikimedia commons.
mention with the proliferation of this one cells, the sea was exhausting his nutrientes and only they could survive the cells capable of using organic compound simple, especially carbon dioxide, as source of carbon, also it is necessary to think that the solar light as source of energy also, this way is born the scientific philosophy of first cells photosynthetic 3.000 million years ago.
The interesting thing two groups of molecules are more important of the alive beings, they are the acids nucleicos, indispensable for the organization and doubling of all the alive beings, the proteins, molecules that take part in all the metabolic processes of growths and of intermediation of the alive beings. There is not known yet how they went so far as to establish the mechanisms of doubling of the acids nucleicos with the relation between proteins and the polinucleótidos.
The scheme of the device designed by Staley Miller, source of image of mastery of wikimedia commons.
The scheme of the device designed by Staley Miller, by means of which the generation of organic compounds demonstrated, from inorganic substances, the gases urinated from the warming of the dissolution contained in the flask of the low part were submitted to unloading electrical, similar that was supposed, that the beams were producing in the primitive ambience, where the stopcocks were allowing to gather samples of the gases that were circulating along the system.
Next we have the coacervados, which are small drops in whose interior they can be stored lípidos and péptidos, in concentration bigger than that there is in the exterior, apart from this in the moment that a coacervado, they coincided a biocatalytic molecule or of protoezima, a molecule seemed to the ribosomas, it is possible to be considered that there appeared the first precursor of the primitive cell procariota. This entity precélular had to have aptitude to work independently, in such a way that it has been demonstrated that a coacervado, with a simpler interface, that a cellular membrane, it is sufficient to allow iónicos exchanges and synthetic internal reactions, which simulate the cellular metabolism.
Bibliography used for this occasion.
Life / Life: The science of the biology / The Science of Biology - Page 11 for David Sadava, William H. Purves - 2009.
Biology: the life in the ground - Page 327 for Teresa Audesirk, Gerald Audesirk, Bruce E. Byers - 2003.
Clinical Embryology - Page 2 for Keith L. Moore, T. V. N. Persaud, Mark G. Torchia - 2009.
