Describe the structure of prokaryotic cells when compared to eukaryotic cells.

mitochondria, and are both used for cellular respiration. This is important evidence that the two are descended from a common ancestor.         However, the two are not completely similar. In fact there are a number of differences between them.         The first visible difference is the Eukaryotes nucleus bound by a double membrane. It is essential for increased efficiency that the DNA related functions of eukaryotes are isolated to a smaller chamber within the cell, this is the function of the Nucleus. However, prokaryotes are much lesser in size and a separate chamber is not needed since all the materials within the cell are comparatively closer than in Eukaryotes. Prokaryotes do have DNA, although it has no physical boundary holding it together, it can be found gathered in the central region of the cell. However, the shape of the DNA itself is different. Within Eukaryotes the DNA is linear whereas in prokaryotes it is circular and therefore has no ends. This shape means that the DNA found in prokaryotes cannot be organised into chromosomes, instead there is one circular DNA molecule and a varied assortment of smaller circlets. Since the prokaryotic cell is much smaller and less complex than the eukaryotic cell it requires fewer genes.         Both prokaryotes and eukaryotes contain a huge number or ribosomes, although the ribosomes themselves differ in complexity. Ribosomes are made up of rRNA (or ribosomal RNA) and a variety of specific proteins. Within a eukaryote the ribosomes are made up of five different types of rRNA and approximately eighty types of protein. When compared with the prokaryotic ribosome made up of three types of rRNA and only 50 types of protein it is evident that the Eukaryotic ribosomes are complicated, they are also larger in size.         The greatest difference between the two cell types is due to their difference in size. Whilst the prokaryotic cell is small and lacks a great amount of space the Eukaryotic cell is huge. This allows the eukaryotic cell to contain a large, complex selection of different organelles within its cytoplasm. Around many of its organelles form their own membranes membranes, separating them from the plasma membrane, this means the eukaryotes can work to optimum efficiency by isolating functions to smaller chambers within the huge cell. In contrast the prokaryotic cell contains no membrane bound organelles independent of the plasma membrane.         In conclusion, the prokaryotic cell is much more simple in its design than the eukaryotic cell as it does not have the space to for complexity. However, it is evident that the prokaryotic cell and eukaryotic cell are linked in many ways and have evolved together.