Biological principles - Term Paper Example

Simply put, all cells have basic molecular mechanisms to synthesize or absorb nutritional elements such as carbohydrates and proteins, are surrounded by a protective layer of membrane so as not to let foreign material invade them and comprise of a genetic structure that regulates their function and aids in proliferation (Gunning & Steer, 1996). Depending on the structure and functional differences, these cells can be classified into two types: prokaryotic cells and eukaryotic cells. The word ‘karyon’ means nucleus, therefore the word ‘prokaryotic’ means before nucleus- that is they do not have a nucleus, and ‘eukaryotic’ means comprising of a true nucleus.

Prokaryotic organisms are always single cellular and mostly bacteria, as contrasted to the single or multicellular eukaryotes in the form of protists, fungi, plants and animals (Black, 2008). Prokaryotic and eukaryotic cells, although mostly different do have some similarities. Both of the types of cells comprise of a cell membrane, that limits the extent of the cells of both types (Black, 2008), by holding in cytoplasm and organelles. Both prokaryotic and eukaryotic cells are also similar due to the fact that they comprise of genetic material in their cells in the form of DNA (Black, 2008), which makes them capable of replicating, thus resulting in the proliferation of cells.

Structurally, the prokaryotic and eukaryotic cells can be divided into their genetic and reproductive structures, and extracellular and intracellular structures (Black, 2008). The genetic material in both the types of cells is similar, however eukaryotes comprise of a double-membrane bounded nucleus that the prokaryotes do not have (Perry etal., 2013). The difference also lies in the shape of the DNA, the prokaryotic DNA is circular in shape whereas the eukaryotic DNA is in the form of multiple strands of the DNA molecule wrapped around proteins and organized in the