A virus is essentially a transporter gene for the express purpose of another cell to infect, to replicate. The virus consists of genetic material, DNA or RNA, protected by a shell of capsid proteins called from. The capsid is assembled generally prepares proteins by viral genetic material. Some viruses do not support, construction of the capsid.
The first type is the virus helical morphology. The virus has a helicalsingle type of protein in the form of a closed tube to genetic material that resembles a spiral staircase. The virus causes to be long, flexible, or short drive. The longer a virus worm, the more it must be flexible, so that forces shot. The length of the viral capsid of the virus's genetic material depends on the length and width of the length and arrangement of proteinsCapsid.
The second type is the icosahedral capsid morphology. This symmetric morphology caused the virus to appear as spherical low magnification, but actually contains capsomeres, ring-shaped structures, the ball is arranged in a pattern similar to a balloon. Capsomeres contain more protein helical virus, a protein is built capsomeres five or six copies of each. Non-icosahedral capsids enclosing the viral genetic material closerhelical capsid. The icosahedral form has been used by R. Buckminster Fuller to create the geodesic dome.
The third type is the morphological enveloped viruses. This virus, in addition to a position with a capsid to acquire a modified form of the cell membrane of an infected computer. There are two levels of this membrane or viral envelope. The inner membrane contains proteins encoded by viral genetic material and proteins encoded by the host geneticwhile the outer layer, and all carbohydrates are strictly from the DNA of the host encoded. The virus viral envelope are some advantages over other viruses naked, the most important of these is the protection of the gains of virus in the host organism. Envelope induces neighboring cells mistakenly believe that the virus is a cell friendly, the results of the virus into the cell is included in the healthy. But this case has disadvantages for the virus. Many viruses withThese envelopes are so dependent on them if the casing was removed, the virus dies.
The last and fourth type is the virus complex morphology. These viruses can not fall into the above categories and, where appropriate, additional structures such as queues or having an outside wall. Examples of complex viruses, bacteriophages, viruses that infect bacteria and smallpox virus. Some bacteriophages have icosahedral head with a spiral tail. The pox viruses are unusualMorphology. The viral genetic material is surrounded by a membrane and two positions of unknown function and for the whole thing is a shell filled with a thick layer of protein.
Viruses vary in size with most in the range of 100-300 nanometers in length. For comparison, average virus next to a flea is like a man standing near Mount Everest. Most viruses are so small that they are not seen with optical microscopy, scanning and transmissionMicroscopes are used to obtain a visual representation of a virus. Viruses contain DNA or RNA, not both. The exception is the human cytomegalovirus, which contains both DNA and mRNA. animal viruses come in all combinations, viruses tend to have one plant and RNA-bacteriophages have double the DNA.
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