* The "rungs" of the ladder: These are made of nitrogenous bases (adenine, thymine, guanine, and cytosine) paired together. Adenine always pairs with thymine (A-T), and guanine always pairs with cytosine (G-C).
* The "sides" of the ladder: These are made of sugar-phosphate backbones. Each backbone consists of alternating sugar (deoxyribose) and phosphate molecules.
The two strands are antiparallel, meaning they run in opposite directions. One strand runs from 5' to 3', while the other runs from 3' to 5'. This orientation is crucial for DNA replication and protein synthesis.
Here's a visual representation:
Imagine a ladder where each rung is a pair of bases (A-T, G-C), and the sides of the ladder are the sugar-phosphate backbones. The two sides of the ladder run in opposite directions.
Important points to remember:
* The unwinding process involves enzymes called helicases.
* The unwound strands serve as templates for DNA replication, where new strands are synthesized using the existing strands as guides.
* The double helix structure is responsible for the stability and information storage capacity of DNA.
