DNA (Deoxyribonucleic acid) is like an instruction manual that carries the genetic information for every living thing. Shaped like a twisted ladder (called a double helix), DNA is made up of four chemical bases: Adenine (A), Thymine (T), Cytosine (C), and Guanine (G). These bases always pair up in specific ways - A with T, and C with G - forming the 'rungs' of the ladder. The sequence of these base pairs creates a code that determines everything from your eye color to how tall you'll grow. When cells divide, DNA can make exact copies of itself through a process called replication, ensuring that each new cell gets the same genetic instructions.
Base Pairing Rules
The rungs of the DNA ladder are made of four nitrogenous bases that pair in specific ways:
- A (Adenine) pairs with T (Thymine) using two hydrogen bonds
- C (Cytosine) pairs with G (Guanine) using three hydrogen bonds