Question

A DNA molecule is said to "unzip" when it is involved with cell division, which means the two strands of the molecule separate in order to combine with new strands. Which of the following statements is consistent with this process of "unzipping"?

(a) To "unzip", a DNA molecule breaks the covalent bonds for its base pairs (the functional groups along the molecule).
(b) Dipole forces between base pairs must be overcome in order to separate the strands.
(c) Hydrogen bonding is involved with holding the strands together.
(d) None of the previous statements are correct.

Answer 1

The answer to your question is: letter C

Step-by-step explanation:

Introduction:

In DNA double helix, each nucleotide attach to another nucleotide with hydrogen bonds because these kind of bonds are not the strongest of the bonds, but are strong enough to mantain the double helix attached and during the process of unzipping double helix can separate easily.

Then:

(a) To "unzip", a DNA molecule breaks the covalent bonds for its base pairs (the functional groups along the molecule). Base pairs are not attached by covalent bonds because these bonds are strong and difficult to break down. So this option is incorrect.

(b) Dipole forces between base pairs must be overcome in order to separate the strands. As it was describe above base pairs are attached by hydrogen bonds, dipole forces is not an option to this example.

(c) Hydrogen bonding is involved with holding the strands together. This i the right option, double helix is attahced by hydrogen bonding.

(d) None of the previous statements are correct. This is not possible because doulbe helix is attach by hydrogen bonding.