Class 12th Biology 2013 Set3 Delhi Board Paper Solution
Question 17
Why and how bacteria can be made competent?
Answer
Bacterial cell is made competent so that it can take up DNA. Taking up DNA is not easy as it is hydrophilic molecule and cannot pass through cell membrane. Bacterial cell can be made competent by treating it with a specific concentration of a divalent cation such as calcium as it increases the efficiency with which DNA can enter the bacteria through it the pores of cell wall.
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