Mechanism of Recombination. Genetic recombination happens during meiosis, a special type of cell division that occurs during formation of sperm and egg cells and gives them the correct number of chromosomes. Since a sperm and egg unite during fertilization, each must have only half the number of chromosomes other body cells have. Otherwise, the fertilized cell would have too many. Inside the cells that produce sperm and eggs, chromosomes become paired. While they are pressed together, the chromosomes may break, and each may swap a portion of its genetic material for the matching portion from its mate. This form of recombination is called crossing-over. When the chromosomes glue themselves back together and separate, each has picked up new genetic material from the other. The constellation of physical characteristics it determines is now different than before crossing-over. Read more: http://www.accessexcellence.org/RC/AB/BC/Genetic_Recombination.php
Channels: Molecular Genetics
Tags: Recombination Mechanism
Uploaded by: watchme ( Send Message ) on 24-11-2010.
Duration: 1m 12s