Class 12th Biology 2016 Set1 Outside Delhi Board Paper Solution
Question 19
Why must a cell be made ‘competent’ in biotechnology experiments ? How does calcium ion help in doing so ?
Answer
DNA being a hydrophilic molecule, can not pass through cell membranes, hence the cells should be made competent to accept the DNA molecules as competency is the ability of a cell to take up foreign DNA. Calcium ion helps in increasing the pore size in cell wall which enables the cell to take up the recombinant DNA.
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