DNA Structure Activity

Problem 3: Grooves in the DNA double helix

Examine the view labeled"phosphate group location". Notice that there are grooves in the surface of the DNA molecule between the phosphate groups. Proteins that interact with DNA often make contact in these grooves. How would you describe the grooves in the DNA surface?

A.	a single groove of uniform size
B.	a single groove that varies in size
C.	two distinct grooves, both of the same size
D.	two distinct grooves, one (the"major groove") is larger than the other (the"minor groove") Notice in the example view that the distance across the major groove is in the range of 18-19 angstroms. The distance across the minor groove is in the range of 12-13 angstroms. For an additional perspective, examine the views labeled "major groove recognition" and "minor groove recognition".