VIRUSES are the smallest of all infectious agents, averaging about 100 nanometers (100 billionths of a meter) in length.About Game Parasite In City Free Download BACTERIA vary widely in size and shape, but tend to be at least 10 times larger than viruses, or at least 1 micrometer (1 millionth of a meter) long.They have so few genes and proteins of their own that in order to reproduce they need to commandeer the machinery of the cells they invade. MULTI CELLULAR ORGANISMS are so large they can usually be seen with the naked eye.SINGLE-CELL ORGANISMS tend to be at least 10 times larger than bacteria, or about.They are single-cell organisms that reproduce independently.

Tapeworms, for instance, can reach a length of 6 meters (20 feet).įood and water are the most common sources of parasite and invading organism transmission. Since most of us eat three times a day and drink water frequently throughout the day, our exposure to these sources is constant. Tap water has been found to be contaminated with harmful organisms. Both plant and animal foods carry parasites, and cleaning and cooking methods often do not often destroy them before ingestion. The CDC (Center for Disease Control) cites food as the catalyst behind 80 percent of the pathogenic outbreaks in the U.S. Most are linked to restaurants and delis where less than sanitary conditions exist - from food preparation and storage to the utensils and servers' hands.Īnimals, just like humans, can become infected with parasites and unhealthy organisms. Internally, contaminated water and food can spread the problem to our pets. Externally, animals become infected by organisms on their bodies, especially on their fur, because of exposure to infected animal wastes. They provide comfort, companionship, protection, amusement, and unconditional love for their owners.įorgetting to wash your hands even one time after handling or cleaning up after your animal can transmit the parasite to you. Yet, pets, like humans, are often victims of serious infections that can unintentionally be passed on to their owners. In fact, there is a whole set of diseases classified as 'zoonoses' (animal-transmitted diseases) in parasitology textbooks.

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