What is a gene?
Genes = sections of DNA that contain coded information to make polypeptides
Coded information = specific sequence of DNA bases.
Polypeptides combine to make proteins, genes determine proteins of an organism.
Enzymes are proteins, genes determine enzymes, therefore determine chemical reactions being controlled by enzymes, control organism's development and activities.
DNA base sequence in gene codes for amino acids that determine polypeptide formed by gene.
NB: DNA codes for amino acids, amino acids determine primary structure of protein, which determines tertiary structure. Therefore DNA indirectly determines tertiary structure and therefore shape of proteins, and therefore their function.
The triplet code
Minimum of 3 bases that code for each amino acid because:
- only 20 amino acids regularly…