The major cellular feature which sets the distinction between a prokaryotic (‘pro’ – before, ‘karyon’ – kernel, nucleus) cell and a eukaryotic (‘eu’ – true, ‘karyon’ – kernel, nucleus) cell is the presence of a nucleus. In prokaryotic cells the genetic material resides in a region of the cytoplasm called the nuncleoid which is not separated from the rest of the cell by membranes and therefore a true nucleus is absent. In contrast, eukaryotes have their genetic material contained within a membrane-bound organelle known as the nucleus which allows for spatial separation of the processes of transcription and translation. The eukaryotic nucleus also contains nucleoli which are regions where ribosomes are organized but this structure is altogether lacking in prokaryotes. Another distinctive feature between prokaryotic and eukaryotic cells is that the prokaryotic DNA is not associated with histone proteins whereas the eukaryotic DNA is. Furthermore, bacterial DNA is normally found as a single circular DNA molecule and multiple and much smaller circular elements known as plasmids. In contrast, eukaryotic genetic material is in the form of a number of linear chromosomes, and plasmids are rare. Despite these structural differences, the genetic material in any cell, be it prokaryotic or eukaryotic, is in the form of deoxyribonucleic acid (DNA) and this is a universal feature of all cellular life forms.
A Comparison of Eukaryotic and Prokaryotic Cells Essay
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A Comparison of Eukaryotic and Prokaryotic Cells
There are two main types of cells in the world. The simplest cells such as bacteria are known as Prokaryotic cells, and human cells are known as Eukaryotic cells. The main difference between each of these cells is that a eukaryotic cell has a nucleus and a membrane bound section in which the cell holds the main DNA which are building blocks of life.
Prokaryotic cells do not have a nucleus. The chromosomes which are found in prokaryotes are usually spread in the cytoplasm. In eukaryotic cells the chromosomes remain together inside the nucleus and there is a clear nuclear membrane that is surrounding the nucleus.
Another difference between the two cells is that, in prokaryotic cells…show more content…
A nucleus is a membrane which can be found in most eukaryotic cells.
The main functions of a nucleus cell are:
• Being involved in cell division
• All the functions of other cells are done under the instruction of the nucleus
• DNA is the building blocks of life which are found within the nucleus.
The main function of the Endoplasmic Reticulum is to produce, store and transport proteins and lipid to most of the cell organelles. The Endoplasmic Reticulum is a large organelle that looks like sheets of folded membranes.
There are two types of Endoplasmic Reticulum the Smooth ER and the Rough ER. you can distinguish that both of the ER’s are different to each other, this is shown in the diagram above that one is smooth ER and the other is rough ER the rough ER has ribsomes attracted to it while the smooth ER does not have ribosomes attached to it. The two ER’s have different function to each other.
Structure of Endoplasmic reticulum: - Sheets of membrane with ribosomes outside (for rough ER). - Forms a tubular network throughout the cell. Function of Endoplasmic reticulum: - Transports chemicals, proteins, and lipids between cells and within cells - The endoplasmic reticulum provides a large surface area for the organization of chemical reactions to take place and synthesis.
In size Ribsomes are about 25 un is diameter. They are arranged in to