How is secondary succession different from primary succession? a. occurs in areas where no life exist b. occurs in areas uncovered by melting glaciers c. occurs in areas where the soil is intact d. occurs in areas inhabited by lichens

primary succession begins with a bare rock and ends with a forest secondary succession begins after a natural disaster where there is a temporary setback after a forest fire or local destruction, but the surrounding area can fill in

prism b but im not for sure

white blood cells or wbc s are mainly 2 types-

1.agranulocytes

2.granulocytes

the monocytes or macrophages of agranulocytes , dendritic cells which are accessory leucocytes, and b cells which is one type of lymphocytes   identify the antigens present on the pathogen's surface. these three cells are called antigen presenting cells(apc) which are phagocytes and destroy the antigens by secreting antitoxins. besides this leukocyte is always plays vital role in the immunity of the body.