Experiments have shown that DNA with a higher G + C content requires a higher temperature to disrupt its double helix than DNA with a higher A + T content.Which statement explains this observation?
A) G and C fit together better than A and T.
B) The two chains assume a parallel orientation when the A + T content is higher.
C) The sugar-phosphate bonds in the backbone are stronger in DNA with a higher G + C content.
D) The covalent bonds between G and C are stronger than those between A and T.
E) G-C pairs form three hydrogen bonds, whereas A-T pairs form just two hydrogen bonds.

Question

Quizplus · Accepted Answer

G-C pairs form three hydrogen bonds, whereas A-T pairs form just two hydrogen bonds. This means that it takes more energy (higher temperature) to break apart the G-C pairs, making DNA with higher G + C content more resistant to disruption.

Experiments Have Shown That DNA with a Higher G