It is most widely used by cells to accurately repair harmful breaks that occur on both strands of DNA, known as double-strand breaks. This process is very frequent in yeast and is largely used as a molecular biology tool in this case.
Homologous recombination is a type of genetic recombination in which nucleotide sequences are exchanged between two similar or identical molecules of DNA.
RNA is a biologically important type of molecule that is found in almost all living organisms, including some viruses.
RNA is chemically similar to DNA, and is in general synthesized in the cells from a DNA matrix of which it is a duplicate. Living cells in particular use RNA as an intermediate genetic carrier to make the proteins it needs. RNA can have many other functions and in particular it can intervene in chemical reactions of the cell.