Various tests have been devised for detecting spontaneous mutations in a population. Some of them are: 1. Replica Plating 2. Mutation Rates in Maize Endosperm and Drosophila 3. Detection of Mutations in Micro-Organisms. Test # 1. Replica Plating: In 1946 Luria and Delbrueck noticed one of the first cases of spontaneous mutation in a bacterial population. When E. coli cells [...]
In this article we will discuss about the definition of gene families. While most prokaryotic genes are represented only once in the genome, some genes in eukaryotes are repeated many times in multiple copies, called gene families, thus contributing to the large size of the genome. In specific cases, multiple copies of a gene are necessary to produce RNAs or [...]
Four major forces are usually listed for changing gene frequencies in populations, namely migration, mutation, selection and random genetic drift. These forces constitute the mechanisms underlying the evolutionary process. 1. Migration: Migration occurs when a large influx of people moves into another population and interbreeds with the latter. The phenomenon called gene flow takes place if one population contributes an [...]