How do hydrogen bonds contribute to the stability of biomolecules?

Hydrogen bonds play an important role in stabilizing the structure of biomolecules such as DNA, proteins, and other macromolecules.

Key points:

1. In DNA:
   • Hydrogen bonds form between complementary nitrogenous bases.
     • Adenine (A) forms 2 hydrogen bonds with Thymine (T)
     • Guanine (G) forms 3 hydrogen bonds with Cytosine (C)
   • These bonds hold the two DNA strands together and give the double helix its stability while still allowing the strands to separate during replication.
2. In proteins:
   • Hydrogen bonds occur between the backbone atoms or side chains of amino acids.
   • They stabilize secondary structures like α-helices and β-pleated sheets.
   • They also contribute to the tertiary and quaternary structure, maintaining the protein’s 3D shape.
3. In other biomolecules:
   • Hydrogen bonds help sugars, RNA, and other macromolecules maintain specific shapes required for their function.
4. Overall effect:
   • Hydrogen bonds provide structural stability without being too strong, allowing flexibility and reversible interactions essential for biological processes.

In short:
Hydrogen bonds hold biomolecules in their proper shapes, making DNA, proteins, and other macromolecules stable yet flexible, which is essential for their biological functions.