Read the following statements regarding the isolation of DNA from a plant tissue: (A) The tissue is first treated with cellulase to break the cell wall. (B) Ribonuclease is added to remove RNA from the cellular extract. (C) Protease is added to remove proteins from the cellular extract. (D) Deoxyribonuclease is added to precipitate the purified DNA. How many of the above statements are correct?

Step-by-step solution

Statement (A) is correct. Plant cells have a cellulosic cell wall, which must be broken down using the enzyme cellulase to release the genetic material. Statement (B) is correct. Ribonuclease (RNase) is used to degrade and remove RNA from the mixture of macromolecules. Statement (C) is correct. Protease is used to degrade and remove proteins (such as histones) from the mixture. Statement (D) is incorrect. Deoxyribonuclease (DNase) would degrade the DNA itself, destroying the target molecule. Instead, purified DNA i