Questions On Viruses Have Genetic Material Enclosed Within A Capsid
3193 Words13 Pages
AP Bio, I
April 17, 2015
Chapter 18, 19, and 20 Review Questions
1. Viruses have genetic material enclosed in a capsid. They are an intercellular parasite. They are also extremely small in size. Their infections can be prevented by vaccines. The virus’s head is the capsid holding the DNA meanwhile its body is called a tail sheath and the tail fibers are the legs coming out of it. The two strategies for viral reproduction are through the lysogenic and lytic cycle. The purpose of the lysogenic cycle is to “build up” the virus. The original virus injects its DNA into the host cell, as the cell undergoes mitosis, the DNA that was from the virus will be replicated as well as the hosts regular DNA. At first the bacteria is known…show more content… Then the cell “explodes” releasing the phages. The differences between them are that the lysogenic cycle is used as a time bomb and that the bacteria takes its time to multiply, then it may enter the lytic cycle. In the lytic cycle, the phages that insert the DNA into the genome get a right away reaction as well as in the lytic cycle is where the viruses are actually made and able to explode from the cell. A temperate phage is the phage that is able to transfer from the lysogenic cycle into the lytic cycle. This is the most dangerous type of virus since it can multiply itself as well as harm many cells at a time, then through the lytic cycle are able to explode out. The lytic cycle is induced when the prophage leave the chromosome of the bacteria, when the lysogenic cycle is multiplying it, it must leave the chromosome for it to go into the lytic cycle.
2. The two examples for viruses in which were considered to be “emerging” are that of the ebola virus and the Hanta virus. The emergence of a virus can be done through a mutation in the old virus, these viruses can jump from one host to another, and they can even come from once isolated populations. The aspects of the modern life can contribute immensely to the emergence of viruses since now there are better methods of transportation, immigration, emigration, and even vacations like tourists and travelers. This can cause the people that came from their home town to bring their viruses with them and