Are Viruses, Prions And Viriods Alive?

834 words - 3 pages

In order to see where viruses, viroids and prions fit into the scheme of life, we need to know what life is and what the properties of life are. The capabilities of viruses, viroids and prions and the diseases they cause. Should they be considered 'alive' if they only contain a few of life's properties because their survival depends on other living cells.Life consists of living things and these living things have cells that have the capacity for "order, reproduction, growth and development, energy utilization, evolutionary adaptation, response to the environment and homeostasis" (Campbell and Reece, 2002). These capabilities represent life in animals, plants and humans.All livings things are susceptible to illness and disease, with viruses being a major cause; they also alter the behaviour of the host of whom they occupy (Villarreal, 2004).The structure of viruses is of "free particles that have a protein coat and a nucleic acid core" (Keeton and Gould, 1967). Viruses have similarities to 'prokaryotic cells' (cells that lack organelles), they share similar "genetic materials and constantly intertwine" (Keeton and Gould, 1967) with each other. The particles 'float' outside the cell, then 'enter' a healthy cell within the host. Once inside, the healthy cell "manufactures new virus particles when the old virus provides the instruction" (Keeton and Gould, 1967). The new particles leave the host cell, move into another cell and repeat the process. Viruses are also capable of entering the cell and remaining 'vegetative' (waiting for the right environmental conditions to emerge), combining their viral DNA with the hosts DNA for replication or as a permanent cell fixture (Keeton and Gould, 1967), it doesn't necessarily kill the cell it enters (Norrby, 1981).There are two kinds of virus, which are based upon the "kind of nucleic acid that makes up its genome" (Campbell and Reece, 2002); either DNA or RNA, a virus never has both. The genomes can have single or double strands of DNA or RNA depending on the type of virus (Campbell and Reece, 2002). Viruses cause disease in "vertebrate, insect, plant and bacterial" forms of life (Norrby, 1981), diseases include (in humans) chicken pox, mumps, measles, small pox, several types of encephalitis, AIDS" and many others, and in plants Tobacco mosaic disease (Campbell and Reece, 2002).Other infectious agents are viroids and prions. Prions are infected proteins that are misfolded and "normally present in brain cells" (Campbell and Reece, 2002). Prions attach themselves to healthy proteins, corrupt the healthy proteins which inturn become prions....

Find Another Essay On Are Viruses, Prions and Viriods Alive?

Prejudice and Discrimination are Alive and Well

1733 words - 7 pages principles. From the beginning of time these two colors have determined your life and what you are able to achieve. Many choose to believe that the times of inequality are over, and that equality is given to all, but evidence is presented daily that America portrays the black man to be inferior to the white race. While equality among all have grown in America over the past decade, minorities still have a hard time reaching their goals in

"The Definition of Life (Or is it?)" Question: What does it mean to say something is alive, conscious, and/or intelligent? Requirements: 1000-2000 words

1529 words - 6 pages ways such as heating, sterilizing, and more. Prions are not made of cells, can’t reproduce on their own, do not grow or undergo division, and do not transform energy. Many people believe that they are not alive, that they’re just one of our own proteins that has gone wrong and that has the capability to cause normal PrP to go wrong, too.Similarly, viruses are a controversial issue. They are somewhere between complicated complexes and


1711 words - 7 pages Report on Prions based on some articles. Excellent.PRIONSPrions have been a mistery for scientists from the day they where discovered. Prions act like viruses but they are not. Their structure and chemistry are unknown. They are believed to be proteins but that is yet to be completely proved.Prion stands for "proteinaceous infectious particles". Prions are known to cause many diseases involved with nervous systems like the brain. They are the

True Nature Of Prions

1330 words - 5 pages The True Nature of Prions Research conducted only over the past couple of decades has unveiled a new type of infectious agent quite unlike all currently known bacteria and viruses. This pathogen, which causes fatal damage to the brain and surrounding central nervous system of humans and other mammals, is called a prion. It has not been completely resolved as to how these agents propagate or how they are composed. The word itself derives

Speech on different pathogens and the diseases they cause

611 words - 2 pages Hello Everyone. I'm here to talk about the difference between prions, viruses, bacteria, protozoans, fungi and macro-parasites. These are all pathogens that cause diseases. I will also be giving examples of the diseases that these pathogens cause.Prions are infectious agents which do not have a nucleic acid genome. Prion diseases are often called spongiform encephalopathies (mad cows disease) because of the post mortem appearance of the brain

Prions the Proteinacious Killer

1032 words - 4 pages disease conveyer from viruses, bacteria, fungi and other known pathogens". It was then determined that scrapie prions 4 contained a single protein that was called "PrP, for 'prion protein'" (Prusiner). It was also found, however, that the protein occurs naturally in healthy animals without any negative effects. It is only when these agents are altered, that they begin to cause problems. The prion-only hypothesis proposes that prions propagate in

The Dangers of Genetically Modified Food

809 words - 4 pages , toxins, viruses, and prions transmitted through GM food (Frenzen). Prions are infectious protein particles, unlike a virus, contains no nucleic acid, does not trigger an immune response, and is not destroyed by extreme heat or cold(). Prions that enter the human body can alter the immune system killing thousands of cells triggering disease in the tissues. Many deaths caused by unknown pathogens are not recognized by doctors in healthcare

Common Features of Some of the World's Deadliest Diseases

2469 words - 10 pages " (NIH, 2013). Diseases are caused by infections that result from microorganisms called pathogens entering a host where they grow causing impairment to normal tissue functions (NIH, 2013). Several different types of pathogens (or infectious agents) can cause infection and disease. They include bacteria, viruses, fungi, protozoa, helminthes (all forms of microorganisms) and prions (proteins) (NIH, 2013 and Kaufman, 2009). Most infectious agents are

Classification and Evolution of Life

562 words - 2 pages scientists argue that viruses are life forms and should be classified into a kingdom. However, many scientists have agreed that things must have seven characteristics of life to be considered alive. The characteristics of life are all living things are composed of cells; all organisms are organized at cellular and molecular levels, energy use, and response to the environment, growth, reproduction, and adaptation.From research and observation, scientists

A close look at Cloning

1181 words - 5 pages viruses or diseases. "Cloning requires a lot of human components. Methods to render human fluids free from viruses are not perfect. Transmission of viral diseases during cloning is still possible. Even if risks of viruses are eliminated, prions continue to be a risk. Prions are small protein molecules, which transmit diseases like the Mad Cow Disease" (Sulekha).In conclusion, cloning could possibly bring us immortality; it could bring back loved

Cell Membrane

1161 words - 5 pages investigations have shown to be true all of the time. Cell theory is not cell law. This is because life forms called viruses, viriods and priods are not composed of cells. Other than these limited exceptions, all life is composed of cells. The cell is the basic unit of life.Many organisms such as bacteria, amoeba, some algae, and yeast are composed of only a single cell. The single celled organisms are described as being "unicellular." However

Similar Essays

Bacteria, Viruses And Prions Essay

1604 words - 7 pages . Web. 29 Mar. 2014. 10. ARE VIRUSES EVEN ALIVE?" Microorganisms: Viruses. Andrew Rader Studios, 1997-214. Web. 29 Mar. 2014. 11. Mandal, Ananya, MD. "Human Diseases Caused by Viruses." Human Diseases Caused by Viruses. AZoNetwork, n.d. Web. 27 Mar. 2014. 12. Yellow Fever." Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, 13 Dec. 2011. Web. 28 Mar. 2014. 13. Yellow Fever Symptoms and Treatment

Understanding Viruses, Bacteria, And Prions Essay

1323 words - 5 pages Many people get viruses, prions, and bacteria confused in multiple ways. However, these are different in several aspects, and once informed about them, people should no longer get them mixed up. For example, the most important and most unique differences between bacteria, prions, and viruses is that bacteria is a living organism, prions are not living organisms, and the debate regarding the living status of viruses has been, and still is

Cybercrime History: Computer Viruses And What Are They?

1977 words - 8 pages like a virus, or worm, Trojan horses and spyware are examples (Morley, Parker, Malicious software, and “More Information About Viruses”). This is not the Trojan horse the ancient Greeks big wooden horse used in the Trojan War (“Trojan horse”). The computer Trojan horse is a type of malware that covers up something else, as a program, like for example a PC game or a utility program (336). Spyware is a software program that is installed without

Trojans,Worms, And Viruses: What Are They And What Can You Do To Stop Them

2339 words - 10 pages figured it out by now, you were looking at pictures online using Google images (for all you Bing fans, I’m sorry but Google is much better). You were downloading pictures from Google and one of them happened to contain a virus and it was downloaded with one of the pictures. How do I know this is a virus? The answer is that I don’t. I didn’t give enough symptoms to diagnose this. To the pros at hacking and security, you may know that viruses are not the