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If a cell is the bedrock and foundation of all life forms, how then was a cell created before it multiplied to form other life forms?

Basically there were atoms of CHOMPS chemical elements floating in space.

After the bigbang explodes came together and from there the first live cell was created, then it evolved

Contemporary biology, in particular biochemistry, has made it clear that living organisms are made up of a variety of chemical elements. Among them there is a small group that are majority in quantity, these are: carbon (C), hydrogen (H), oxygen (O) and nitrogen (N), or briefly and as a mnemonic rule: CHON. In addition, there are other elements in much smaller quantities that are also essential for living organisms and that make possible the amazing phenomenon that we call "life". Among them we can mention, using their chemical symbols: Na, K, Ca, Mn, Mg, S, P, Si, Cr, Fe, Cu, Zn, F, Cl, I, Mo and others.

It should be clarified that the majority are found as ions and not as elements, since in many cases the latter are very reactive. For example, elements of the alkali metal family, such as Na and K, are explosive in contact with water. Obviously, it is not in this chemical way how they intervene in cellular biochemistry, but as ions (or cations, to give them their more specific name) Na + and K +. The same can be said of some elements that give rise to ions of opposite sign (anions), such as fluorine (F). This is the most reactive element of all, it is an extremely irritating gas and its inhalation represents a danger. The F - ion, called fluoride, has lost that reactivity, is soluble in water and is fundamental for cell physiology, mainly for use in teeth and bones.

Now let's go to another branch of science: cosmogony, which is the branch of astronomy that studies the evolutionary behavior of the universe and the origin of its characteristic features. According to this science the universe had a beginning, which is located 13 ± 2 billion years ago. That is, there is uncertainty about the precise time, but there is a very high probability that it has happened in the time interval between 11 and 15 billion years ago, with the highest probability occurring in the vicinity of 13 billion years.

The theory that best explains this event is known as the "Big Bang" (or Big Bang in English). It also states that within 4 minutes of our vertiginous expansion universe, its chemical composition was 76% hydrogen (H, with atomic number one), 24% helium (He, with atomic number two) and insignificant amounts of lithium (Li, with atomic number three). The atomic number indicates how many protons the nucleus of the atoms of each element has.

Figure 1. Timeline for the history of Universe life

There was no other element. Only the first two, if any three, positions of the table of the periodic classification of the elements had been occupied. With this raw material the chemistry was, evidently, quite limited. There was not enough variety (diverse chemical elements) to constitute systems as complex as life.

Where did the C, the N, the O, the Cu, the Zn and so many other elements with an atomic number greater than three arise and which, as we have already seen, are indispensable constituents of a living system? The cosmogony clearly answers this question, based on nuclear physics, as we shall see below.

Nuclear physics and cosmogony

The explanation offered by the cosmogony about the origin of the other elements involves the stars, which according to their mass were producing in the course of their evolution (or life) the different elements heavier than the H and the He.

The star conditions are such that they favor the realization of the different nuclear reactions that are forming the other elements of the table of the periodic classification that we know today.

Due to its very high temperature (for example, in the surface of our Sun the temperature is between 4 700 and 6 000 K and in its center to 20 million K) each star is a huge plasma sphere. Plasma is the state of matter that is characterized by having atomic nuclei devoid of all their peripheral electrons and shaking at high speeds, just like electrons.

Under these conditions it is possible that the nuclei collide with each other even though there are repulsive forces between them (because they all have a positive charge). At lower temperatures, with less thermal agitation, nuclear reactions are not possible. The nuclei would be accompanied by their electrons and simply would not touch each other, they would be diverted by the repulsive forces between charges of the same sign (negative, of their respective peripheral electrons). However, at high temperatures the nuclei do touch, collide and fuse together, like two droplets of water that collide and form a larger droplet. These are the nuclear fusion reactions that give rise to the process of nucleosynthesis, that is, to the synthesis of new nuclei, of new elements (heavier).

For a star like our Sun, by nucleosynthesis and starting from the mixture of H and He, could reach the formation of carbon and oxygen. Stars of greater mass are required to generate other heavier elements during their evolution. And still others (different) are synthesized in the final stages of life of these stars more massive than the Sun, during explosive processes of unimaginable violence.

The material produced by nucleosynthesis in the stars reaches to be dispersed by the space, in particular the one that is derived from those stars that are massive with an explosive and furious death.

In short, the mixture of H and He of the initial universe has been changing slowly thanks to the formation of stars of mass similar or greater to that of our Sun. At present the chemical composition of the universe is 75% hydrogen, 23 % helium and 2% of all other chemical elements. Slowly, the space of the universe has been subtly enriched by those elements heavier than the H and the He, in particular of C, O and N, and also of others that are essential for the development of life.

This material enriched in elements heavier than H and He will be dispersed and, under the appropriate conditions, a solar nebula can be formed, a protosol ignited by the nuclear reactions between the H and the He and forge a sun. Perhaps, planets are also formed to constitute a planetary star system, perhaps with characteristics similar to ours. But this history of the formation of the Planetary Solar System and the Earth must be told, in more detail, in another issue of Teacher's Mail.

Stellar physics and the emergence of life

In the preceding paragraphs, I have implicitly classified the stars according to their mass into two classes: those with a mass similar to the Sun, and those with a greater mass. There can not be stars much smaller than the Sun; if the mass of the latter had been lower by only 9%, the temperatures required to initiate nuclear fusion reactions would not have been reached, there would be no sun and we would not be here to tell.

It happens that according to the magnitude of its mass will be the duration of a star or, to put it another way, "the duration of its life" (since a star arises, burns or uses its fuel in nuclear fusion reactions, this one sooner or later it ends, and therefore, without more fuel, the star dies or dies).

All stars start their combustion with the primal mixture of H and He. Massive stars consume their fuel much faster than stars with sun-like mass. In fact, they consume it a thousand times faster. This makes a big difference. Indeed, thanks to the massive stars it was possible to synthesize elements of greater atomic number. This at the same time introduces a much broader variability in chemistry, which surely makes the emergence of life more feasible. However, although appropriate to produce diverse elements, the massive stars have a life too short to serve as a luminous and energetic source to possible planets that surround them and that could be the cradle of life.

On the other hand, the smallest stars, like our Sun, only produce light elements such as carbon and oxygen, and perhaps in that way the emergence of life would be less feasible or perhaps impossible because sufficient complexity and variety would not be achieved. chemical functions. However, because of their long life, these lower mass stars can be a reliable source of light and energy for a sufficiently long time to planets that could present the necessary conditions for the emergence of life. Our Sun is in the middle of its life (its total duration will be approximately 10 billion years).

To put it simply, there is a kind of complementation of functions, for the purposes of the origin of life in the universe, between both types of stars.

Fig. 2 Re presentation is the chemistry of different events in the history of the Universe. Assuming a total age of 13 million years. (If we suppose an age of 15 million years, the prcentajes would fit respectively to 11.16%, 37.4% and 70%).

In our Planetary Solar System, we, on Earth, have been able to verify the existence of a great variety of elements, we have identified them and built a periodic classification table. Now we know that these elements, of which the Earth and all its inhabitants are made, were created in previous generations of stars, from their remains or ashes. The solar nebula that gave rise to the Planetary Solar System must already contain those heavier elements, vestiges of stars that shone before our Sun.


After having flown over cosmogony, nuclear physics and biochemistry we can make at least one inference that has to do with the title of this article.

The emergence of life in the universe could not be an early event in its history. The appropriate chemical elements had to be had, which arose after a long succession of events. It was to be expected first that the first stars were formed, perhaps a billion years after the Great Explosion. Then, they burned in nuclear fusion reactions. Massive stars take about 10 million years to consume. At least one generation of these stars had to burn to begin to disperse new elements to the interstellar vacuum. Then, a planetary star system enriched in the new elements and that contained a small star like our Sun, to be able to provide a contribution of luminous energy sufficiently prolonged and constant (the Sun began to ignite in nuclear fusion reactions 4.6 billion years ago). Life arises on Earth (as prokaryotic unicellular life) at 730 million years after the emergence of our Planetary Solar System, and only 4.6 billion years later, life adopts, among many other forms of life, the human form.

Taking into account these numbers, assuming a duration of the universe of 13,000 million years and considering a history similar in duration to that of the Earth, a unicellular life could have arisen somewhere in the universe at about 1 740 million years (1 000 + 10 + 730 million years) from the Big Bang. Put another way, after a time equal to 13.4% of the current universe age.

The emergence of intelligent life like ours (thus qualified by us) would have taken much longer: 5 610 million years (1 000 + 10 + 4.6 billion years). That is, it could have appeared after a time equal to 43% of the current age of the universe, not before, not earlier.

Considering this, the flowering of our humanity has been late, very late in the history of the universe. We exist at the tip of time, at the tip of the current age of the universe. There has been plenty of time (57% of the current age) for intelligent life to blossom in other corners of it. In fact, just when our Planetary Solar System was being formed, there could already be outbreaks of intelligent life in the universe (Figure 2).

Another aspect that deeply impresses me when I evoke this scenario is the unimaginable violence and the enormous temperatures through which each and every one of the elements that constitute me, that constitute us, had to pass; to be finally thrown that matter into the cold and black void of interstellar space ... waiting for a new beginning.


This is a really good question. 

It is speculated on but it is extremely difficult to come up with a proven theory on exactly how that happened. What has been known since the 1950's is that conditions on early Earth are capable of producing all the amino acids needed as raw material for DNA and other molecules essential in cells. That was proven in the Miller-Urey experiment in 1952.

There exist two types of cells. Eukaryotes have differentiated organelles and a separate nucleus containing the DNA of the cell. Prokaryotes are much simpler and they have everything mixed up in one cytoplasm separated by the cell membrate from the environment. The first are thought to be prokaryotes. It is conveivable that the currently existing prokaryotes evolved from simpler ones. The crucial step is the formation of the cellular membrane and the ability to self-copy. 





We may never have the capacity to demonstrate without question how life initially advanced. However, of the numerous clarifications proposed, one emerges – the possibility that life developed in aqueous vents profound under the ocean. Not in the superhot dark smokers, but rather more serene undertakings known as soluble aqueous vents.

This hypothesis can clarify life's most interesting component, and there is developing proof to help it.

Prior this year, for example, lab tests affirmed that conditions in a portion of the various pores inside the vents can prompt high centralizations of huge atoms. This makes the vents a perfect setting for the "RNA world" generally thought to have gone before the primary cells.

In the event that life evolved in antacid aqueous vents, it may have happened something like this:


Dilute permeated into recently shaped shake under the ocean bottom, where it responded with minerals, for example, olivine, creating a warm soluble liquid wealthy in hydrogen, sulfides and different synthetics – a procedure called serpentinisation.

This hot liquid sprang up at soluble aqueous vents like those at the Lost City, a vent framework found close to the Mid-Atlantic Ridge in 2000.


Dissimilar to the present oceans, the early sea was acidic and wealthy in broken down iron. While upwelling aqueous liquids responded with this primordial seawater, they delivered carbonate rocks loaded with modest pores and a "froth" of iron-sulfur bubbles.


Inside the iron-sulfur bubbles, hydrogen responded with carbon dioxide, framing basic natural atoms, for example, methane, formate and acetic acid derivation. A portion of these responses were catalyzed by the iron-sulfur minerals. Comparative iron-sulfur impetuses are as yet found at the core of numerous proteins today.


The electrochemical angle between the antacid vent liquid and the acidic seawater prompts the unconstrained development of acetyl phosphate and pyrophospate, which act simply like adenosine triphosphate or ATP, the concoction that forces living cells.

These particles drove the development of amino acids – the building squares of proteins – and nucleotides, the building hinders for RNA and DNA.


Warm streams and dissemination inside the vent pores concentrated bigger particles like nucleotides, driving the development of RNA and DNA – and giving a perfect setting to their advancement into the universe of DNA and proteins. Development got going, with sets of particles equipped for delivering a greater amount of themselves beginning to command.


Greasy particles covered the iron-sulfur foam and immediately shaped cell-like air pockets. A portion of these air pockets would have encased self-duplicating sets of atoms – the main natural cells. The soonest protocells may have been slippery substances, however, regularly dissolving and improving as they coursed inside the vents.


The development of a compound called pyrophosphatase, which catalyzes the generation of pyrophosphate, permitted the protocells to separate more vitality from the inclination between the antacid vent liquid and the acidic sea. This old catalyst is as yet found in numerous microscopic organisms and archaea, the initial two branches on the tree of life.


Some protocells began utilizing ATP and additionally acetyl phosphate and pyrophosphate. The generation of ATP utilizing vitality from the electrochemical slope is idealized with the advancement of the catalyst ATP synthase, found inside all life today.


Protocells facilitate from the principle vent pivot, where the regular electrochemical slope is weaker, begun to produce their own inclination by drawing protons over their films, utilizing the vitality discharged when carbon dioxide responds with hydrogen.

This response yields just a little measure of vitality, insufficient to make ATP. By rehashing the response and putting away the vitality as an electrochemical inclination, be that as it may, protocells "set aside" enough vitality for ATP generation.


When protocells could produce their very own electrochemical angle, they were not any more fixing to the vents. Cells left the vents on two separate events, with one mass migration offering ascend to microscopic organisms and the other to archaea.