BIOLOGY 1A03 Lecture Notes - Lecture 17: Kary Mullis, Dna Replication, Thermal Cycler

• School: McMaster University
• Department: Biology
• Course: BIOLOGY 1A03
• Professor: Kim Dej

Document Summary

Bio 1a03 applications of dna replication lecture 17: cells have an innate copying mechanism which allows the dna to replicate semi- conservatively. In 1985, kary mullis developed the polymerase chain reaction in a tube which amplified millions of copies of dna from samples. However, dna polymerase is needed which is tolerant to high temperatures (such as taq polymerase) to catalyze the polymerization of each daughter strand within the tube: each cycle of pcr has 3 stages: denaturation, annealing and extension. This process creates an exponential growth of dna, 1 cycle = 2 strands, 2 cycles = 4 strands, 3 cycles = 8 strands etc: to begin pcr, the dna double helix is unwound through high temperatures. The mixture is heated to denature the strands of dna. The thermocycler then cools to allow the primers to anneal to their complementary sequences on the dna template strands on either side of the dna sequence of interest during the annealing phase.