Studies on immune responses in afferent and efferent lymph of lymph nodes draining the tissues have contributed to the concept that primary immune responses are generated in the lymph nodes with a delay before antigen-specific effector cells arrive at the affected tissue.
Lightning strikes the ground approximately 25 million times each year in the U.S. According to the NWS, the chance of an individual in the U.S. being killed or injured during a given year is one in 240,000. Assuming an average life-span of 80 years, a person's odds over their lifetime becomes one in 3000.
Florida has more injuries and deaths attributed to thunderstorms tâ¦han any other US state. The city of Tampa is also billed as The Lightning Capital of the Nation for its huge number of thunderstorms. In one month (June 1994), more than 50,000 lightning strikes occurred in the Tampa/St. Petersburg metropolitan area.