Variation is useful for the survival of species over long time. but the variants have unequal chances of survival. explain this statement.

Well, if I had a mutation in which I had wings, and another human had a mutation in which he had to live underwater because he had gills, and the water all evaporated, his strand of mutation would die. same with subtle mutations. One mutation may be better for an environment that another mutation.

The arrangements of lipids in the membrane makes the cell semi permeable .