You are referring to a "three-dimensional sphere" as the usual "sphere" (strictly speaking a "ball"- "sphere" refers to the surface of the ball). The "two-dimensional" sphere then would be the disk whose surface is a circle, and the "one dimensional sphere" would be an interval whose "surface" is the two endpoints of the interval. The "volume element" would be just "dx" and there is no "surface area element" because the surface of a "one-dimensional sphere" is not continuous.