Why Do Viruses Cause Cancer?

Viruses are microscopic particles that invade and take over both eukaryotic and prokaryotic cells. They consist of two structures, which are the nucleic acid and capsid. The nucleic acid contains all genetic material in the form of DNA or RNA, and is enclosed in the capsid, which is the protein coating that helps the virus attach to and penetrate the host cell. In some cases, certain viruses have a membrane surrounding the capsid, called an envelope. This structure allows viruses to become more stealthy and protected. There are two cycles in which a virus can go into: lytic and lysogenic. The lytic cycle consists of the virus attaching to a cell, injecting its DNA, and creating more viruses, which proceed to destroy the host. On the other hand, the lysogenic cycle includes the virus attaching to the cell, injecting its DNA, which combines with the cell’s DNA in order for it to become provirus. Then, the provirus DNA may eventually switch to the lytic cycle and destroy the host.

A virus is a small capsule that contains DNA or RNA, viruses, unlike bacteria are not self sufficient and need a host in

On encountering a host cell, the retrovirus attaches itself to receptors on the surface of the host cell’s membrane. Once inside the cell, the capsid opens, releasing RNA and reverse transcriptase into the cell’s cytoplasm.

The virus fuses with the cell’s plasma membrane. The capsid proteins are removed, releasing the viral proteins and RNA. Reverse transcriptase catalyzes the synthesis of a DNA strand complementary to the viral RNA. Reverse transcriptase catalyzes the synthesis of a second DNA strand complementary to the first. The double-stranded DNA is incorporated as a provirus into the cell’s DNA. Proviral genes are transcribed into RNA molecules, which serve as genomes for the next viral generation and as mRNAs for translation into viral proteins. The viral proteins include capsid proteins and reverse transcriptase (made in the cytosol) and envelope glycoproteins (made in the ER). Vesicles transport the glycoproteins from the ER to the cell’s plasma membrane. Capsids are assembled around viral genomes and reverse transcriptase molecules. New viruses bud off from the host cell.

A lot of the time when a virus come into contact with the host or as we may know it, the cell, it can insert its genetic material into its host, literally taking over the host's functions. Some viruses may remain dormant inside host cells for long periods, causing no obvious change in their host cells, but once stimulated new viruses are formed, self-assemble, and burst out of the host cell, killing the cell and going on to infect other cells. All this is just a constant battle between the host and cell. Without a host cell, viruses cannot carry out their life-sustaining functions or reproduce. They cannot synthesize proteins, because they lack ribosomes and must use the ribosomes of their host cells to translate viral messenger RNA into viral proteins. Viruses cannot generate or store energy, but have to derive their energy, and all other metabolic functions, from the host cell. Sometimes the virus will not be in the cell but outside functioning as coat for the protein. Viruses cause a number of diseases in humans most commonly heard of ones are, smallpox, the common cold, chickenpox, influenza, shingles, herpes, polio, rabies, ebola, hanta fever, and AIDS are examples of the diseases caused by viruses. Even some types of cancer but not all. As Sun Tzu wrote in The Art of War, “All warfare is based on deception”. He could have easily been describing the ancient battle between virus and host

The virus is now travelling inside a sac made from your cell 's membrane. The virus’s genetic material enters the nucleus, and the virus is cloned. Now thousands even millions of new virus’ are in now your body, and taking over

Some viruses duplicate by forcing their DNA into ours and these genes are sometimes passed down through generations. In the beginning, the new genes can still do most of the same functions as the original virus genes; they are still able to force their host cells to create viruses

The virus replicates in the cytoplasm of the host cell. DNA replication and transcription may start immediately as the virus itself contains enzymes for replication and transcription. It does not rely on the host cell enzymes to begin replication (Koplow 2003). First, the DNA and RNA polymerase are made, along with other transcription

Viruses are responsible for some of the most life threatening diseases affecting humans such as HIV and Ebola. They are found in every ecosystem and are considered to be the most abundant biological entity on earth. Viruses do not only infect humans but are also capable of infect any living organism. Lacking all basic biological machinery necessary for replication, viruses are by definition obligatory intracellular parasites and thus must infect other life forms in order to replicate. This characteristic makes them an invaluable tool for the study of molecular cellular processes

It can then activate and rapidly reproduce the B cells, certain proteins that the virus releases allow the infected B cells to survive the germinal centre reaction and form resting memory B cells. Thereafter the virus slows its release of proteins to a rate where it’s still able to avoid any responses the hosts immune system may have.

Viruses, after entering a host cell, integrates its genome with the host cell’s DNA using the enzyme reverse transcriptase. During normal DNA replication, the virus’ genome will be replicated to produce more viral particles. During this process, host cell genes can be triggered by viral genes

The developed virus works in the same as the common herpes virus as the infected cells burst releasing more of the virus and infecting nearby cells. The modifications allow the virus to-

Viruses are microscopic parasites that thrive outside the host body and are able to reproduce. They are about eight times smaller than bacteria (live science). Viruses are known for their ability to infect people and make them sick. Their ability to evolve has let them stay alive through generations. Viruses are considered to be mankind’s deadliest enemy. Due to their ability to evolve, viruses have been able to survive through generations despite scientists and doctors efforts to stop them. Without a host cell, viruses cannot carry out functions or reproduce. They derive their energy from the host cell. (Thesis)

Viruses cause a wide variety of human diseases. They travel easily person to person contact or touching contaminated areas. Once in the body they reproduce quickly after enduring cells. Respiratory infections are caused by Rhinovirus, coronavirus and adenovirus are the cause of a common cold. Influenza virus infect your upper respiratory system and can potentially spread to the lungs causing pneumonia. Digestive system infections such as the stomach flu is caused by a virus such as calicicirus and astrovirus. Skin infections are another disease caused by viruses. Chicken pox is a disease in which itchy fluid-filled bumps on the skin form and eventually bust or scab over. This virus is called the varicella virus. It also can cause shingles which

One strand of the RNA is transcribed into a RNA- DNA double helix, whereas the breakdown of RNA uses ribonuclease- H. Without delay, polymerase completes the cycle with the other DNA strand to form a double helix. Soon after the complication of the polymerase the next enzymes, integrase, takes over. This enzyme is required to cut the end of every third prime and then transfer the DNA into the nucleus. As a result, of combining with the host cell genome that now contains the genetic information of HIV. The cytoplasm gets invaded by the messenger RNA where new viruses are synthesized. Protease, one of the last of the enzymes, helps create the infectious virus. Finally, when the virus becomes mature by the RNA strands and enzymes they come together and form the capsid. It would leave the host cell ready to infect other cells and replicate by billions per day. (“How HIV Infects a Cell.”) Furthermore, with help of antiretroviral therapy, it can block the steps of the viral life cycle and control the