The Theories Of Virus Origin

When we hear the word virus, we usually think of something that makes us sick. A virus is an ultramicroscopic infectious organism that, having no independent metabolic activity, can replicate only within a cell of another host organism. A virus consists of a core of nucleic acid, either RNA or DNA, surrounded by a coating of antigenic protein and sometimes a lipid layer surrounds it as well. The viral genome provides the genetic code for replication, and the host cell provides the necessary energy and raw materials. To fight viruses, we use vaccines. While some may infect a broad range, other viruses can only infect certain kinds of cells. Vaccines are made of inactive, dead or weakened virus cells or protein antigens that can no longer infect

The biological significance of this article is due in part to the fact that viruses are being considered as partway-living things. Even though they are only halfway living, per se, they are still an important part of the study of living things because of the unique way in which they “live” and continue to reproduce by taking advantage of host cells. The information in this article relates to biologists in that viruses provide an entirely different element of potential life, as they are a cause for reconsideration when it comes to defining and determining life and non-life forms. This

It is often argued whether viruses are living or not. Those who don’t believe that viruses are living generally base their opinion off of the fact that they do not follow the basic definition of “life”. They do not carry out life-sustaining functions on their own like normal organisms. On the other side of the argument, some believe that viruses are in fact, living beings, which is where I rest my opinion.

Viruses, Plagues, and History, written by Michael Oldstone, is an insightful and highly educational book that details the history of, that’s right, viruses and plagues. Through typically dry, yet engaging prose, Oldstone recounts what seems like all of it while simultaneously bringing to light the contributions of those brave scientists who asked themselves, “why.” He focuses his attention on some of the most notable viruses such as smallpox, yellow fever, measles, polio, and later he focuses on more contemporary battles against disease.

The mutation of existing viruses, the spread of existing viruses from one host species to another, and the dissemination of a viral disease from a small, isolated population that can lead to widespread epidemics.

Where it is still unclear the origins of viruses, one thing is clear, they are a very important part of the horizontal gene transfer, which drastically increases genetic diversity.

virus” (AAV), because they are able to “insert their genetic material at a specific site

After looking at many articles I believe that viruses are not alive. Even though in the beginning I believed they were. For an object to be alive it needs to have certain characteristics such as being able to: grow, develop, have a purpose, reproduce, adapt, and have cells. A living thing could reproduce which means they would make offspring. Viruses don't have the ability to grow and develop on their own. Viruses don’t have the ability to reproduce on their own without the help of a keeper

1. In the 19th century researchers realized that some diseases such as hand foot mouth and also rabies were caused by particles that acted like bacteria. Which means virus's are alive because the particles would need t be alive to still contaminate people.

A virus is a capsule containing genetic material, even smaller than bacteria. The main task of virus is to reproduce. However, viruses need a suitable host to

There is still a great deal of information to learn from the study of viruses and the continued exploration of the viral genome is crucial in understanding how viruses communicate, transmit from host to host and evade immune responses. The ever-change nature of the viral genome has shown us that the most dangerous viral infections of today may be undermined by newer and more effective viruses, resulting in catastrophic outcomes. Through the study of viruses, it is the hope of the scientific community to be ahead of the viral curve, preventing infections before they even

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

To consider something as living there are a few requirements it must fulfil such as to grow, reproduce, respond to stimuli, adapt to their own environment, made from cells and can use and gain energy1. Viruses have only recently been considered as a contender for being classed as a living organism as they have played a major part in the evolution of all cells2 which shows that viruses must have contained some of the early key components that ancient cells possessed. RNA genomes were present before the Last Universal Common Ancestor (LUCA) as ancient cells had them as well as viruses, so viruses probably originated before other cells. However, some scientists have said there is an area between living and

From the sequence scientists were able to determine that virus probably began its life in an animal then mutated before picking up the power to infect people.

The protective capsid helps the virus escape detection and destruction during the invasion of the host. When the virus reaches the target cell, biochemical reactions between the capsid and cell wall allow the virus to latch on and inject its genome into the cell’s interior. Once inside, the viral genetic material insinuates itself into the host’s DNA or RNA. In an efficient feat of natural bioengineering, the host cell’s genetic machinery now does the rest of the work for the virus. The cell, which had already been making copies of its own genome, now also replicates that of the virus. Coded within the viral material is the blueprint for making more copies of the viral genome. Further instructions command the production of capsids and directions for assembly of new viruses. After the host cell becomes engorged with viruses, it explodes, sending the new