DNA Structure Activity

Problem 1: Identifying the location of phosphate groups.

DNA (and RNA) are polymers made up of five-carbon sugars, organic nitrogen-containing bases, and phosphate groups. Where are phosphates located on DNA?

A.	the outermost surface of the DNA The electronegative oxygen atoms of the phosphate groups have a negative charge, and are in position to interact with cations in the cell that help stabilize DNA through ionic interactions.
B.	partially exposed and partially buried
C.	buried in the interior of the molecule