PSYC 2001 Study Guide - Y Chromosome, Homologous Chromosome, Synapsis
Document Summary
Chapter 10- genetic recombination: two molecules of dna with similar sequence are brought into close proximity, enzymes nick the dna backbones, exchange the ends, and reattach them. In this case, the final result is two recombined dna molecules. Basically, recombination is when parts of two chromosome switch with each other. So they are basically crossing over, like a-a and b-b become a-b and b-a. If combined strains grew on minimal medium, then recombination occurs: several hundred out of 100 million grew. Prototrophs: strains that are able to synthesize amino acids. Auxotroph: mutant strains that are unable to synthesize amino acids. Replica plating: identifies and counts genetic recombination in bacterial colonies. Complete medium: has full complement of nutrient substances. Auxotrophic mutants: will not grow on media missing nutrients. Basically, there are two cells, f+ and f-. When they are conjugated, the genetic material is replicated from f+ to f-. This then makes the f- cell into a f+ cell.
