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 [...]
In this article we will discuss about the meaning of transposable elements. The chromosomes of E. coli and other prokaryotes contain discrete moveable segments of DNA called transposable elements, which can be translocated to other locations. Such DNA sequences can move from one position on a chromosome to another, and from one DNA molecule to another. They are detected when [...]
In this article we will discuss about the definition of cistron. The earlier geneticists considered a gene to be the smallest unit (a bead or a chromomere) on a chromosome which could be distinguished as a functional unit, or as a unit of recombination, or as a unit of mutation. It was also believed that crossing over occurred only between [...]