BIOL 1406 Lecture 16: Biology notes Ch. 17
Document Summary
Our dna accounts for specific traits by dictating the synthesis of proteins. Proteins are the links between genotype and phenotype. The process by which dna directs protein synthesis is called gene expression and includes two stages: transcription translation. Rna is the intermediate between genes (dna) and the proteins for which they code. Transcription is the synthesis of rna under the direction of dna. Translation is the synthesis of a polypeptide, which occurs under the direction of mrna. So, a dna code provides instructions to build proteins. There are 20 amino acids, but there are only four nucleotide bases in dna. The flow of information from gene to protein is based on a triplet code: a series of three- nucleotides called a codon. These triplets can code for all the amino acids. Agt at a particular position on a dna strand codes for the amino acid serine. All 20 aas have a triplet dna code (or several)
