Topic 30Biology

D1.2 Protein synthesis

DNA → mRNA via transcription (RNA polymerase, antisense template); mRNA → polypeptide via translation at the ribosome (A/P/E sites, tRNAs, the triplet code with redundancy + universality + start/stop signals); sickle-cell as a worked example of a single base change causing disease; HL extensions cover pre-mRNA processing (5' cap, poly-A tail, splicing + alternative splicing) and post-translational modification (cleavage of preproinsulin → insulin, ubiquitin/proteasome recycling).