Sister chromosome exchanges are recombination events that occur between homologous chromosomes and are often the result of exposure of the cell to DNA damaging agents.
Cross over, or recombination, is the exchange of chromosome segments between non sister chromatids in meiosis. Crossing over creates new combinations of genes in the gametes that are not found in either parent, contributing to genetic diversity.
Active genes are found in the EUCHROMATIN of eurkaryotic chromosomes.
Euchromatin is a type of chromatin which is composed of DNA, RNA and proteins and which is enriched with active genes. Euchromatin is the most active portion of the genome inside the cell nucleus. For humans, 92% of their genome is made up of euchromatin.
