DNA Structure

Structure of a DNA Molecule: Extended

• DNA, or deoxyribonucleic acid, serves as the repository of genetic information for all living organisms.
• It comprises two intertwined strands forming a structure known as a double helix.

• Nucleotides are the building blocks of DNA, each composed of a sugar, a phosphate group, and a nitrogenous base.

• All nucleotides in DNA share the same phosphate and deoxyribose sugar, differing only in the base attached to them.
• There exist four distinct bases in DNA: Adenine (A), Cytosine (C), Thymine (T), and Guanine (G).
• Each base on one DNA strand pairs specifically with another base on the complementary strand, thereby maintaining the double helix structure.
• Adenine always pairs with Thymine (A-T), while Cytosine always pairs with Guanine (C-G).

• The phosphate and sugar components of nucleotides form the structural "backbone" of the DNA strand, akin to the sides of a ladder.

• The sequence of bases in DNA holds instructions for protein formation.