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The Different Characteristics Viruses, Bacteria, and Prions

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Viruses, bacteria, and prions are microscopic, living beings. All three can be found inside and outside hosts. Bacteria and viruses are more similar with each other than a prion with either one. None are even closely related, though. The three of them have different reproduction methods, structures, and choices of hosts. These are not the only differences by a long shot, but it is a start.
A virus is an infectious agent. It is very small in size. They cannot reproduce without the use of a host. A capsid surrounds the virus. The capsid is made of protein subunits. It has three main functions, first, to protect the nucleic acid within from digestion. Secondly, hold proteins that attach to certain host cells for reproduction. Lastly, to provide proteins that help the virus enter the host cell during penetration. The other main part of a virus is nucleic acid. This is DNA or RNA that holds the genetic material for protein synthesis.
Viruses have two different reproduction cycles, the lytic and lysogenic cycles. The lytic cycle has five stages: attachment, penetration, biosynthesis, maturation, and then, release. In attachment, the virus capsid uses its host specific proteins and combines with a receptor on the host cell. Then comes penetration, where the viral DNA is inserted into the host cell, through the receptor, past the membrane. Biosynthesis follows, viral components are synthesized and the host cell starts replicating the virus. After biosynthesis is maturation. In maturation the viral components assembly, meaning that all the virus structures come together to prepare for the next stage of release. Finally, there is release, where the new viruses leave the host cell to infect more cells. Some of the things different betwee...

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