Why are water striders able to "walk on water"?

Water striders can walk on top of water due to a combination of several factors. Water striders use the high surface tension of water and large hydrophobic legs to help them stay above water. Water striders use this surface tension to their advantage through their highly adapted legs and distributed weight.

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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.

oxygen +1 most likely