Which of the following statements about the 5' end of a polynucleotide strand of DNA is correct?
A)The 5' end has a hydroxyl group attached to the number 5 carbon of ribose.
B)The 5' end has a phosphate group attached to the number 5 carbon of ribose.
C)The 5' end has thymine attached to the number 5 carbon of ribose.
D)The 5' end has a carboxyl group attached to the number 5 carbon of ribose.
E)The 5' end is the fifth position on one of the nitrogenous bases.

Question

Quizplus · Accepted Answer

The 5' end of a DNA strand has a phosphate group attached to the number 5 carbon of ribose. This phosphate group is important in forming the phosphodiester bonds between nucleotides, which make up the backbone of the DNA molecule. The complementary 3' end of another DNA strand has a hydroxyl group attached to the number 3 carbon of ribose, and it is this hydroxyl group that participates in phosphodiester bond formation with the phosphate group of the 5' end.

Which of the Following Statements About the 5' End of a Polynucleotide