Are Viruses Alive?
1. Describe how a virus differs from bacteria.
Most Viruses are harmful and their only purpose is to invade a host cell, reproduce and destroy the host cell in the process. Close to 99% of bacteria are beneficial with only a few that cause diseases. Life on earth could not exist without bacteria. Bacteria produce nearly half of the oxygen found in the atmosphere. Viruses have no cells, nucleus, cytoplasm or cell membrane. Viruses consist of tiny particles of nucleic acid enclosed by a coat of protein. Viruses are smaller than bacteria and can only be seen by an electron microscope. Bacteria are small but larger than a virus and have a single cell of a prokaryotic type. Bacteria lack a nucleus and organelle. All bacteria have one molecule of DNA. Viruses have one strand of DNA or RNA but not both. Viruses can’t function on their own and depend on a host cell for their energy and reproduction. Viruses cannot reproduce unless they get inside a living host cell. Once a virus attaches itself to a host cell it dissolves a hole through the membrane and goes to the nucleus to force the host cell to replicate the virus. Viruses are parasites. Bacteria can function on their own, metabolizing and converting carbohydrates to energy. Bacteria reproduce by growing to twice its size and then splitting into two cells. Viruses are not classified and grouped into a level of biological organization like other life forms are. Bacteria are classified to have two levels of biological organization, Atoms and Molecules. 2. According to the article readings, website reviews and lecture notes we were asked to review: • Name the characteristics of life viruses seem to lack as they differ from the lecture outline. Considering all characteristics of life described in the lecture outline beginning with the hierarchy of Biological Organization to Evolve: Viruses have the biological organization of atoms and molecules because they are...
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