NEETZoologyBiotechnology - Principles and Processes
The major steps involved in the isolation of genetic material (DNA) from a biological sample are given below. Arrange them in the correct chronological sequence. A. Addition of chilled ethanol B. Treatment with macromolecules-degrading enzymes like protease and ribonuclease C. Spooling of the precipitated DNA D. Treatment with specific enzymes like lysozyme, cellulase, or chitinase Choose the correct answer from the
Options
- AD, A, B, C
- BD, B, A, C
- CB, D, A, C
- DD, B, C, A
Correct answer
B. D, B, A, C
Step-by-step solution
The isolation of pure DNA involves several sequential steps to remove other cellular components. First, the cells must be broken open to release DNA along with other macromolecules. This is done by treating the sample with specific enzymes like lysozyme (for bacteria), cellulase (for plant cells), or chitinase (for fungus) (Step D). Next, the RNA is removed by treatment with ribonuclease, and proteins are removed by treatment with protease (Step B). Once the DNA is purified from these macromolecules, it is precipit