Question

In the Watson-Crick model of DNA structure: a. nitrogenous bases are covalently attached to carbon 1' of deoxyribose T can form three hydrogen bonds with either G or C in the opposite strand. b. the distance between the sugar backbone of the two strands is just large enough to accommodate either two purines or two pyrimidines. c. both strands run in the same direction, 3' -> 5'; they are parallel. d. phosphate groups project toward the middle of the helix, where they are protected from interaction with water.

Answer 1

d. Phosphate groups project to the middle of the helix where they are protected from interaction with water.

Step-by-step explanation:

a, b and c are incorrect statements of the Watson-Crick model of DNA. Only d is true

• T (thymine) can only form 2 hydrogen bonds with Adenine (A) on the opposite strand.
• The distance between the sugar backbone of the 2 strands can only accommodate one purine and one pyrimidine .
• The DNA strands run anti-parallel to each other