BLESS YOUR GRADES AT LEAST TAKE A LOOK!!

Which of the following characteristics do many fish that live in the coral reefs possess? (Choose all that apply.)

A) They are thin so they can make sharp turns around the reefs.
B) They are able to eat the polyps.
C) Many eat zooxanthellae.
D) They are brightly colored so they can hide in the reef.

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.

in 1859, charles darwin set out his theory of evolution by natural selection as an explanation for adaptation and speciation. he defined natural selection as the "principle by which each slight variation [of a trait], if useful, is preserved".