3. What type of organisms have an anterior concentration of sensory structures and nerves? What is this phenomenon called Animals with bilateral symmetry display cephalization. Animals with radial symmetry display oral/aboral sides. Animals with bilateral symmetry develop heads on their ventral side. Animals with asymmetry form brains on their posterior ends.

Animals with bilateral symmetry display cephalization.

the most speciallized is b. grizzly bear

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.