NEET2013ZoologyBiotechnology - Principles and ProcessesActual
During the process of isolation of DNA, chilled ethanol is added to:
Options
- Aprecipitate DNA
- Bbreak open the cell to release DNA
- Cfacilitate action of restriction enzymes
- Dremove proteins such as histones.
Correct answer
A. precipitate DNA
Step-by-step solution
Chilled ethanol is used to precipitate DNA out of a mixture of biomolecules. Low temperature protects DNA by slowing down the activity of enzymes that could break DNA apart while ethanol, being a dehydrating agent removes water molecules bound to DNA and making it visible. Chloroform is used in the extraction process of DNA to remove proteins bound to DNA. Related Theory There are five basic steps of DNA extraction that are consistent across all the possible DNA purification chemistries: 1) disruption of the cellul