DNA

The structure of DNA
DNA molecules are made up of strands consisting alternately deoksyribose and phosphorous molecules, forming a double helix. A base is attached to each sugar molecule, the four different bases being A (adein), T (tymin), G (guanin) and C (cytosin), and each containing nitrogen.

The bases are connected by weak hydrogen bonds. A and T and C and G make respectively make up base pairs, and therefore one can precisely determine the order of one strand if one knows the exact order of the other.



Genes

A gene is a sequence of nucleotides in the DNA. It contains a template for a specific protein that performs a function. There are about 20 000 genes in each of our cells, which is what our 46 DNA molecules contain of.