Prokaryotes And Eukaryotes Similarities

With only two classifications of all organisms, Eukaryotes and Prokaryotes, the question about similarities and differences by these two types of cells is often raised. A lot of the curiosity revolves around how they may be related, share evolutionary links or what makes them diverse. While Prokaryotic cells and Eukaryotic cells share a few similar cellular structures and basic molecular mechanisms that could indicate links, the amount of differences that exist between these two types of cells can revoke any ideas of common ancestry between these two classifications of organisms. The endosymbiotic theory (Lynn Magulis, 1980’s) suggests that eukaryotes originate from prokaryotes in the scenario that a prokaryote engulfed a mitochondria, chloroplast

Referring back to the genetic code, even though prokaryotes and eukaryotes share the same genetic code, the genome possessed by eukaryotes is far more extensive and complicated than that of prokaryotes. Some mechanisms also contribute to a difference in the genetic model; focussing on the process of transcription - prokaryotes have a simpler method and they only utilize a single type of RNA polymerase, whereas in Eukaryotic cells there are three different types of RNA polymerases (pol I, pol II, pol III) specific to each group of RNA.This also plays a part in the far more complex nature and structure of eukaryotic cells. Extending on genetic differences, it is essential to make note of the difference in DNA structure. Differences are also evident in chromosomal structure, prokaryotes tend to have a simpler structure of a single loop of chromosome often referred to as the plasmid. Where as chromosomes in eukaryotes have a more linear shape and are arranged in multiples. Chromosomes are more compact in eukaryotes and are held together as a structure called nucleosomes, this consists of DNA being wrapped around histones. There are exceptions of prokaryotes that still contain histones that also help with the formation of nucleosomes e.g some

Whereas eukaryotes contain 80S ribosomes (60S and 40S subunits) and consist of 40% RNA and 60% proteins . This emphasis on the idea that the synthesis of proteins in eukaryotes is on a larger scale than prokaryotes and relates to the more complex protein structures that exist in eukaryotes. In general, translation is much more rapid process in prokaryotes, as transcription occurs in the cytoplasm and so the mRNA has quick and easy access to ribosomes for translation to occur. Whereas in eukaryotes, mRNA would need to be transferred to the cytoplasm to be used for translation. Therefor, translation in eukaryotes adds only one amino acid per second whereas about 20 amino acids can be added in one second in