Active Immunity
When B cells and T cells are activated by a pathogen, memory B-cells and T- cells develop. Throughout the lifetime of an animal these memory cells will “remember” each specific pathogen encountered, and are able to mount a strong response if the pathogen is detected again. This type of immunity is both active and adaptive because the body's immune system prepares itself for future challenges. Active immunity often involves both the cell-mediated and humoral aspects of immunity as well as input from the innate immune system. The innate system is present from birth and protects an individual from pathogens regardless of experiences, whereas adaptive immunity arises only after an infection or immunization and hence is "acquired" during life.
Read more about this topic: Immunity (medical)
Famous quotes containing the words active and/or immunity:
“The most intellectual of men are moved quite as much by the circumstances which they are used to as by their own will. The active voluntary part of a man is very small, and if it were not economised by a sleepy kind of habit, its results would be null.”
—Walter Bagehot (1826–1877)
“There is immunity in reading, immunity in formal society, in office routine, in the company of old friends and in the giving of officious help to strangers, but there is no sanctuary in one bed from the memory of another. The past with its anguish will break through every defence-line of custom and habit; we must sleep and therefore we must dream.”
—Cyril Connolly (1903–1974)