Why viruses are considered to be alive or dead.
Viruses have the characteristics of both living and non-living organisms, so some scientists say that they are living and some say they are not. Viruses contain nucleic acids and proteins, like that of a living organism. With the help of a host cell a virus can reproduce, but not by mitosis like other living organisms. Also if a virus is not in a living cell it will die, unlike a living organism.
The lytic and lysogenic of a cold sore virus.
A cold sore virus starts off in the lysogenic cycle. In this cycle the virus is dormant, it makes proteins, called a prophage and divides many times. When it enters the lytic cycle you can see the virus on your lip as a big sore. The protein's for building phages have been collected and during the lytic cycle they get built. They then break the wall of the host and run wild causing havoc. The virus goes back and forth between lytic and lysogenic cycles. That is why you will get cold sores at around the same time every year. The virus never dies but goes dormant.
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How does the body fight against pathogen such as viruses and bacteria?
There are three different ways that our bodies fight against pathogens antibodies, phagocytosis, and interferon. Phagocytosis is when the white blood cells in your body identify a virus and they "eat it" by engulfing it and breaking it down with enzymes in their lysosomes. Antibodies are proteins made by white blood cells and they connect to the pathogens, once they are all connected together they get eaten by the phagocytes. Interferon is a protein made by an infected, dying host cell. It signals to other host cells telling them that it is being attacked and activates immune cells to kill virus.
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Compare and contrast the process of binary fission and conjugation.
During Binary Fission one parent cell is splitting into two identical daughter cells. Since they are identical they have the same advantages and weaknesses. This helps and works against the viruses and bacteria, this means that if it has a immunity to an antibiotic it will be carried down to it's daughter cells but if it is killed by a certain antibiotic then so will its daughter. They can also reproduce faster because they don't need a mate to have offspring. Conjugation is when two viruses attach and there is a donor cell that gives a part of its genetic information to the recipient cell. This is helpful because the recipient cell still has its set of genetic information and that will create offspring that is different than the parent cells. They can't reproduce as fast because they have to find a mate to mate with but what the two parent cells are killed by may not kill the daughter cell. This also mean that they may not have the same immunity as the parent cells.
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besides conjugation what are the other ways a bacteria can alter its genetic information?
There are two other ways this can happen, either by transformation or transduction. Transformation is when a bacteria dies and has say a immunity to one certain type of antibiotic, then another bacteria comes along. That bacteria can pick up the genetic information of the bacteria that died and now it will have all the immunities of the bacteria that died. Thus altering the genetic information of the living bacteria. Transduction is when a virus attaches to a bacteria cell and takes some of its genetic material and attaches to another bacterium and transfers the genetic information into that bacterium.
The evolution of antibiotics and how the use of antibiotics are contributing to the development of superbugs.
Antibiotics are being used, abused, and overused. They are making the viruses evolve faster to catch-up to the changing antibiotics. People are going in to the doctor and asking for antibiotics for the smallest thing or trying to get antibiotics for say, for the common cold. When antibiotics are used the virus is being fought off yes, but when an even worse infection comes along that same antibiotic can't be used to fight off that virus. Viruses are also evolving to fight against the antibiotics and are sending that genetic information to other viruses. The viruses that have evolved to fight against viruses are given the name "super bugs".
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