Formation Of Protocells Essay, Research Paper
Today, we’ve realised that the very first life on Earth was indeed originated from abiotic surroundings. In fact, organic molecules have been successfully generated from abiotic elements by scientists
To understand how this creation of life from abiotic material occured, we have to consider a critical idea. Life originated from its abiotic surroundings. Thus, it is important for us to learn about the physical and chemical environments of the primitive Earth. The atmosphere of primitive Earth consisted of reactive, naturally availabe, molecules: Nitrogen (N2), water (H2O), methane (CH4), and ammonia (NH3), etc. These molecules what was needed to create life — in fact, the percentage of hydrogen, oxygen, nitrogen, and carbon, together consists 99.5 % of all matters. In fact, the percentage of essential elements of life — C, N, O, H, P, and S — are quite similar from individuals to individuals.
Energy wise, the Earth had plenty from a variey of sources Radiation: from the cosmic and radioactive isotope decays UV light: there were no protective ozone layer and thus immense heat. Electrical discharge from the never ending lightning caused chemical reactions to occur very often and there was also another source of heat from the young earth crust which was volcanically active.
For most chemical reactions to take place, a spark of electricity is needed, and this was provided by the lightning in the atmosphere. Amino acids basically consist of hydrogen, nitrogen, oxygen and carbon. Due to all of the lightning chemical reactions took place between molecules of N2 and H2, thus these molecules formed Amino acids.
A famous American scientist Dr Fox, was able to show how amino acids, the building blocks of proteins found in all living things, could spontaneously organize themselves into “microspheres.” These cell-like structures, in the right conditions — perhaps like those found shortly after the Earth was formed — grow and multiply. A trace of these microspheres where found in fossils believed to be 3.4 billion years old. This once again inforces the theory of amino acids being the first building blocks on earth.
These amino acids, with the help of fatty acids, were able to form protocells.
These cell-like organisms were able to survive and reproduce in a very limited environment because of their simplicity. Over time, some of these protocells came together and shared their specialization in a symbiotic relationship.
These cells, somehow got life . They began producing membranes to protect what they had inside them. The fatty acids had lined up on the water so as rain dropped into water they were and the cells were bounced out of the water, the got layered with fatty acids and thus membranes were formed.
The cell developed Glycolosys, a organelle which produces energy, or, as it is better know ATP s(the fact that all living organisms today have some way of getting, or have producing ATP s show that they came from one thing ).
These protocells divided and regrew by a process called binary fusion. However they were constantly needed to change in order to survive. The thus formed organelles to help them with this. They formed organelles for things like respiration, as the pure oxygen available then was fatal to the cell( the same way it is fatal to the tetanus germ). It formed organelles to help with everything from making ATP s to helping it to move and thus the protocells of yester-earth had been able to form into more and more complex systems due to the process of endosymbiosis.
These organisms were able to survive and reproduce in a very limited environment because of their simplicity. Over time, some of these protocells came together and shared their specialization in a symbiotic relationship. These colonies of protocells eventually became the cells we know today.
The Symbiotic Theory provides an explanation for the evolution of multicellular organisms known as Eukaryotes. The theory states that these organisms evolved not by random genetic mutation as previously believed, but by a number of cell combinations. The simpler, less complex Prokaryotic combined or merged together into a single host cell to the extent of being an inseparable structure and formed today’s multicellular Prokaryotes.
This theory basically states there were many cells living on their own, but as more cells formed, they began to compete for recourses. They began to live in communities in order to get recourses more easily. Each cell had taken up a specific task and only did that task. Thus all these little cells began to change to enable it to do its task more easily.
Thus all these little cells became more and more dependent on each little organelle in its community. And as the rain fell onto the water, the fatty acids wrapped these communities up in a membrane and thus we have the cells which are alive today.