Problem 67 - Chemistry: An Atoms-Focused Approach

Question

What kind of intermolecular force holds together the strands of DNA in the double-helix configuration?

Step-by-Step Solution

Answer

Answer: Hydrogen bonding is responsible for holding the strands of DNA together in the double-helix configuration.

Step 1: Identify the DNA Structure

DNA, or Deoxyribonucleic acid, is a complex molecule that carries genetic information for the growth, development, functioning, and reproduction of all known organisms. DNA has a double-helix structure, consisting of two long chains (strands) of nucleotides coiled around each other, connected by pairs of complementary bases.

Step 2: Identify the Complementary Base Pairing

In DNA, there are four different bases: Adenine (A), Thymine (T), Cytosine (C), and Guanine (G). The bases on one strand of the DNA pair up with the bases on the other strand, through hydrogen bonding, following two specific complementary base pairing rules: Adenine (A) pairs with Thymine (T), and Cytosine (C) pairs with Guanine (G).

Step 3: Determine the Intermolecular Force

Hydrogen bonds are a type of intermolecular force that occurs when a hydrogen atom (H) is bonded to a highly electronegative element (such as nitrogen (N), oxygen (O), or fluorine (F)) and is attracted to another electronegative atom. In the DNA double-helix structure, the hydrogen bonds form between the complementary base pairs (A-T and C-G) across the two strands. These hydrogen bonds are responsible for holding the two strands of DNA together.

Step 4: Conclusion

In conclusion, the intermolecular force that holds together the strands of DNA in the double-helix configuration is hydrogen bonding. These hydrogen bonds form between the complementary base pairs (A-T and C-G) and are essential for the stability and functionality of the DNA molecule.