Viruses & Cells Comparison Essay Example | Topics and Well Written Essays - 500 words

Viruses & Cells Comparison - Essay Example They are classified differently because of the inherent structural and functional differences. Unlike living cells which can reproduce on their own, viruses have to rely on other cells for them to reproduce. Viruses lack other cells parts like the plasma membrane, ribosomes, and the cytoplasm. They, therefore, infest a living host and use its cells to reproduce. Secondly, living cells are self-sustaining while the viruses are not. Living cells are able to survive on their own because they have all the required structures and proteins which allow them to carry out life-sustaining processes and functions. Viruses, on the other hand, have to rely on a host cell or organism. The third difference is that living cells can synthesize proteins while viruses cannot. Cells have ribosomes and can easily synthesize proteins on their own. Viruses lack these ribosomes and have to rely on the host cells to be able to translate its messenger RNA into the viral proteins. According to Grifo and Tahara , viruses do not have the ability to generate and store energy in form of adenosine triphosphate (ATP) as in the case with living cells. They derive their energy and all other metabolic functions from the host living cells. They do this by using basic building materials like Amino acids, lipids, and nucleotides from the host organism. Finally, viruses cannot respond to stimuli as it is the case of the living cells. Viruses are inert chemicals which cannot perform critical life functions or even responding to stimuli.