What is it that makes diseases caused by viruses and bacteria hard to treat?
Influenza viruses and others continually change over time, usually by mutation. This change enables the virus to evade the immune system of its host so that people are susceptible to influenza virus infection throughout their lives. Bacteria mutate in the same way and can also become resistant if overtreated with antibiotics. –Submitted by Helle Gawrylewski, Johnson & Johnson 9. How old are the oldest fossils on earth? Answer: About 3.8 billion years; they’re bacteria-like organisms. –Submitted by Paul Nurse, 2001 Nobel Prize Winner; Rockefeller Institute 10. Why do we put salt on sidewalks when it snows? Answer: Adding salt to snow or ice increases the number of molecules on the ground surface and makes it harder for the water to freeze. Salt can lower freezing temperatures on sidewalks to 15 degrees from 32 degrees. –Submitted by Arthur Knudsen, Bridgeton, N.J.
