Essay on The Adaptive Parasite

We hear how Henrietta’s cells helped learn and find cures about so many viruses, but what is a virus? A virus is a microscopic organism that only replicates within the cells of a host organism. One of the most well known viruses Henrietta’s cells helped us with was the polio virus. Polio virus is a viral infection of your central nervous system. Polio virus is a lytic virus meaning that, polio goes through reproduction and the cells bursts. Polio virus’s most extensive outbreak was in the early to mid-1990s. Thankfully the vaccine was released in 1995.

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

Some evolutionary biologists believe that since viruses are not alive, they are unimportant when considering evolution; this view places viruses in a category of merely secondary influencers of evolution. However, genetic information is directly exchanged with living organisms within the web of life. Also, virus genomes can permanently colonize their hosts, leading researchers to conclude that the cell nucleus itself originates from viruses. Prokaryotic cells did not merely gradually adapt until they formed a nucleus and became eukaryotic cells. Instead, the nucleus could have come from a persistent, large DNA virus that, within prokaryotes, made a permanent home. In conclusion, although viruses may not be technically defined as alive, they provide a link and form the boundary between biochemistry and biology, and are an integral component within the study of life.

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.

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.

Viruses are coated genetic material that invade cells and use the cell's apparatus for reproduction.

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

It was a challenge for researchers to find a cure because of how new these strands were, and there was also pressure to find these cures soon due to how fast this virus could have, and in some cases did, move through populations. Shortly after his expedition to Kitum Cave, Gene Johnson says this quote from Louis Pasteur, a 19th century microbiologist, “Chance favors the prepared mind.” This quotation applied to the situation because those who knew how to handle this virus ended up being far more successful than those with no experience. Therefore, the author aims to point out that those who treated the virus with ignorance had created danger by approaching their situations with carelessness, which ultimately leads to

For example, viruses do not use energy and raw materials to grow and reproduce, and they are not made of one or more of the basic fundamental units of life – a cell. Compared to a cell, which includes organelles that enable the structure to grow and reproduce, a virus can only reproduce if another cell is present and that cell has organelles that the virus can inject its own DNA or RNA into and use it for its own replicating or mutating purposes. Viruses are made of a protein coat or capsid with its DNA or RNA genetic material enclosed inside of the capsid. In comparison, in addition to having organelles that use energy to help the cell develop, grow, and reproduce with the help of DNA, the cell by definition is enclosed in a membranous boundary,

Proteins are the end products of the decoding process that starts with the information in cellular DNA meaning viruses have genetic materials in it which living things also have. They said that vast repertoire of protein structures, called “folds,” are encoded in the genomes of all cells and viruses. This folds in protein helps viruses reproduce which is also one of the characteristics of living things. Another evidence is that there is a new study that analyzes, three-dimensional structures found in proteins. There are 442 protein folds found in viruses meaning “You can build a tree of life just by this.” says Caetano-Anolles. This also shows that there are unique components the virus have that show viruses are alive. The author used the protein structure of viruses to support their claim that viruses are considered to be

Viruses can replicate themselves but only within a host cell in which they hijack as they do not own any translational machinery, so it is unable to create new RNA or DNA fragments or create a new set of virions5. In the first stages of viral replication the virus will attach itself onto a host cell via the glycoprotein spikes which eject off the capsid – this is called adorption6. The virion will then transfer its genomic material whether its RNA or DNA into the host cell via penetration of plasma membranes and this occurs through receptors binding to receptor sites and activating a chain of reactions6,7. The virus will the inject its own genomic material into the host cell which causes the host cell to use its replication techniques to replicate the foreign genome meaning its expressed by the host cell – hijacking the cell6. The genomic material that is now in the cell will be replicated as the cell is infected and will express these new characteristics of the virus instead of being able to carry out its own job. The newly produced proteins and enzymes will now mature within the host cell and group together to form new virions and viruses. After these are fully matured the enzymes produced will catalyse the cell membrane of cells and allows the newly produced viruses to be released into the extracellular environment6. This process of replication is also the way in which viruses adapt to their environments another component of being classed ‘alive’ because they

Viruses are not entirely alive for the reason they can’t reproduce on their own. A virus is independent of a host and it’s considered a obligated parasite, whose structure is consist of nucleic acid that’s surrounded by a coat of protein called a capsid. Viruses have evolved over time, about 10 million years ago, and they still have been evolution over time from prokaryote cells or eukaryotic

Viruses can’t reproduce on their own. Viruses rely entirely on a host cell in order to replicate themselves. Once inside a cell, they can hijack it in order to reproduce, and when they do, they reproduce like crazy. This is one of the reasons that biologists debate whether or not a virus is, in fact, alive or not. Viruses also do not have metabolic processes that run independent of their host. Without a host, they lie dormant, and don’t have any processes going on (4). Viruses also lack a strong organization to their cells. They don’t have ribosomes, which makes the transformation of mRNA into amino acids very difficult, as they need to use their host’s ribosomes. These three facts are the biggest blockades for viruses to being considered

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

Since the beginning, humanity has overcome diseases that could potentially wipe out the human race. From earliest forms diseases such as measles to modern day pandemics such as AIDS, mankind has survived throughout history. Though diseases have plagued society it was only after the outbreak of the HIV virus in 1981 that brought to attention the dangers of incurable diseases. Before this time, with World War I and II, and the Cold War, public fear was based on the potential chance of a nuclear destruction of the planet. Since the outbreak of the HIV in 1981, public anxiety has been displaced from nuclear winter to that of microbial plagues. The enemy was now no longer a visible foe but that of an unknown contagion with no knowable cure. Recently in 2009, with the outbreak of the Swine Flu (H1N1) Virus public alert of the dangers of contagions increased. Science Fiction films since the outbreak of HIV have reflected the public fear of the unknown and unbeatable contagions. Films such as Outbreak (1995), Contagion (2011) and the recent World War Z (2013) have shown audiences a creative window of possible outcomes of an epidemic and what man would do in order to stop the