Although this is still an emerging field of research, it gives viruses the potential to one day do more good than harm. Antibiotics do not stop viruses. Also called the flu. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit.
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You cannot download interactives. People get sick when another organism, big or small, invades their body and infects them. These infectious agents come in all shapes and sizes, and all of them pose different threats to the human body.
Some are microscopic, such as bacteria or viruses, which attack human bodies on the cellular level. Others are larger, like fungi, which are unicellular or multicellular organisms that grow on and feed off organic material, including humans. Finally, parasites such as tapeworms can find their way inside the human body and feed on blood and nutrients without killing their host. Learn more about infectious agents and their impact on human health with this curated resource collection.
Even the most basic parts of a cell can enable complex cellular processes, and multifunctional organelles expand these capabilities to make advanced activities possible for higher life-forms. Organelles are specialized structures that perform various tasks inside cells. Fever, headache, fatigue, muscle weakness and pain, sore throat, dry cough, and a runny or stuffy nose are common and may develop rapidly. Gastrointestinal symptoms associated with influenza are sometimes experienced by children, but for most adults, illnesses that manifest in diarrhea, nausea, and vomiting are not caused by the influenza virus though they are often inaccurately referred to as the "stomach flu.
Since that time, a tremendous amount of research focusing upon the causative agent of AIDS has been carried out and much has been learned about the structure of the virus and its typical course of action.
HIV is one of a group of atypical viruses called retroviruses that maintain their genetic information in the form of ribonucleic acid RNA.
The activity of the enzyme enables the genetic information of HIV to become integrated permanently into the genome chromosomes of a host cell. License Info. Image Use. Custom Photos. Site Info. Contact Us. The Galleries:. Photo Gallery. Silicon Zoo. Chip Shots. DNA Gallery. Amino Acids. Religion Collection. Cocktail Collection. Screen Savers. Win Wallpaper. Mac Wallpaper. Movie Gallery.
Virus Structure Viruses are not plants, animals, or bacteria, but they are the quintessential parasites of the living kingdoms. Send us an email. Davidson and The Florida State University.
These cells are also either erythroid or myeloid, depending on the culture conditions employed. Most of the erythroid cells transformed by E26 are erythroblast-like, but a significant number are more mature, including erythrocyte-like cells as well as some cells that appear to be aberrant in differentiation.
Both erythroid and myeloid Etransformed cells produce infectious virus and express P E26, the putative gag-myb-x transforming protein of the virus. Thus E26 is a virus that is capable of generating factor-dependent transformed cells in two different hematopoietic lineages.
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