What is the difference between virus and cell bacteria?
Viruses are extremely small organisms that are 100 times smaller than a single cell bacteria. A virus can cause illness in humans, animals, and plants ranging from mild to severe. A mild virus can cause influenza in humans however a more severe example of a virus would be HIV/AIDS. There are four main stages in a virus life cycle which begin when a virus particle reaches a susceptible host (someone with a low immune system). This particle attaches itself using surface proteins that act like ‘keys’ to lock into the host’s vulnerable cells. DNA or RNA from the virus particle is passed inside the host’s cell where it then gains control of its functions and begins to replicate itself. Once the virus has finished replicating, the new virus particles break off from the host cell then begin the process all over again. Viruses can only reproduce inside the host cell until the thousands of copies fill the cells and burst them open. The virus can then leave the body via the bloodstream, airways or digestive tract. A virus can cause diseases such as measles, mumps, rubella, chickenpox, and rabies. The most common symptoms of a virus are runny noses, chills, aches and pains, abdominal cramps, coughs, shortness of breath and diarrhea. Treatment of viruses includes rest, hydration, antiviral medication (such as Relenza) and immunizations. Viruses can remain dormant in the human body for years and re-appear when trauma or stress occurs.