For rain and very light snow, 2WD will likely work fine, and for most vehicles, front-wheel drive is the preferred setup. (For performance cars, RWD is preferred, but AWD, if available, can increase traction. AWD is fine for most normal snow conditions or for light-duty, off-pavement excursions.
Microorganisms that cause diseases are called pathogens. They are specialised to infect body tissues where they reproduce and cause damage that gives rise to the symptoms of the infection. The body fights back by mobilising its immune system to fight off the infection.
Pathogenic diseases Pathogenic diseases are caused by the presance of one or more pathogenic agent in the body, including viruses, bacteria, fungi, protazoa, multicellular parasites and aberrant proteins known as prions.