What is the body’s second life of defense? when does it take effect?

If the pathogens get past the first line of defense (ex. A cut) then then the second will take affect. There is no specific second line of defense, but there are phagocytic cells that ingest and destroy any pathogens.

The answer is atmosphere. there are four spheres of the earth: 1. geosphere (from greek word 'geo' = ground), 2. hydrosphere (from greek word 'hydro' = water), 3. biosphere (from greek word 'bio' = life), and 4. atmosphere (from greek word 'atmo' = air). a magnetosphere is a region of space around astronomical objects controlled by the magnetic field of that object. through the process of elimination, since lightning is present in the air, it can be found in the atmosphere.