1. Viruses are they ALIVE or NOT....?
Everyone has a different views on this depending on what facts they believe to be the most important. In my opinion I think that viruses are not alive this being because they don't fall into several of the characteristics of life, which are:
1) All life is made up of at least one cell 2) All life has to eat 3) All life grows-increasing its biomass 4) All life reproduces itself 5) All life responds to its environment 6) All life adapts-evolves to survive in its environment 7) All life maintains internal and external homeostasis 8) All life ends Looking at the above list of the characteristics of life viruses don't fit into many of those categories. Viruses are in capable of reproducing, the one thing they do is multiply themselves but this is only done by forcing the host cell to help. Wendell's Stanley's experiment with the Tobacco Mosaic Disease was he left the filtrate out, crystals had formed and the water had evaporated. When he poured water back onto the crystals he placed this on healthy leaves and they became diseased. Since all life dies when water is sucked out of them, viruses since they are capable of being crystallized they must not be living. Another fact that supports the fact that viruses are not living is unlike all other living things viruses do not contain the living component of cells; cell organelles, cytoplasm. Viruses are also incapable of growing, although they do replicate this is not the same as actually growing and increasing the biomass. This is why I believe that viruses are not living. |
2. Lytic and Lysogenic cycles of a cold sore (Herpes Virus)
3.Our bodies defence
4.Compare and Contrast the processes of binary fission and conjugation
5. Ways bacteria can alter genetic information....
Aside from conjugation, there are two other ways bacteria are able to alter their genetic information. Transduction is one way bacteria can change their genetic information. This is when genes from viruses are introduced to bacteria. A type of virus called a bacteriophage attaches itself to a bacteria and injects its own DNA. Eventually this virus will have integrated its DNA into the bacterium's DNA. The bacterium cell with the viral DNA inserted in its DNA will then multiply, producing multiple cells with the viral DNA attached to their own DNA. These cells will now enter the lytic cycle and will burst and release new viruses. These viruses with the vial DNA and Bacterium DNA will then affect more cells causing the genes of bacteria to alter. This is how transduction alters bacteria's genetic information. Transformation is a second way to alter the genetic information of a bacterium. During transformation genes are picked up from the environment. The scientist Griffith was the one who discovered transformation. During his experiment he took the disease causing and heat killed bacteria mixed it with live harmless ones and inserted the mixture into the mice. The mice then developed pneumonia and died, which was thought shouldn't have happened. Griffith dissevered that inside of the mice's lungs were disease causing bacteria. By doing this experiment Griffith discovered that the harmless strain of bacteria had developed the heat killing bacteria's disease causing ability. Basically transformation can cause one strain of bacteria to be altered into another. The above are the two ways, besides conjugation that a bacteria can change their genetic information.
|
6. "SuperBugs"
Have you ever thought because you have a cold you need antibiotics? Well you shouldn't. Studies are showing that the more we use antibiotics the greater chance bacteria will become resistant. When penicillin was first discovered to be an antibiotic it was capable of fighting against several infections. However now that it has been used for so long the bacteria "Superbugs" are becoming antibiotic resistant. Over use of the antibiotics is one contributing factor to the development of superbugs. Another contribution is not taking all the drugs you were prescribed. Even if you feel better you must follow the doctor's instructions and finish the bottle. This being because the bacterium that is still alive and resistant to the antibiotics will then reproduce through binary fission producing two identical daughter cells which will then divide and produce daughter cells. Eventually the bacteria population is full of the bacterium that are antibiotic resistant. Conjugation, transduction, and transformation are all ways that these bacteria can distribute their resistance even more. Because of our overuse and not taking all the pills supplied this is contributing to the development of "Superbugs".