Question

The term "competent" refers to

• A. Increasing the competition between cells
• B. Making cells impermeable for DNA
• C. Increasing the efficiency with which DNA enters the bacterium through pores in its cell wall
• D. Making cells permeable for divalent cations

Answer 1

The correct option is C Increasing the efficiency with which DNA enters the bacterium through pores in its cell wall

• Transformation is a process by which a cell takes up naked DNA fragment from the environment, incorporates it into its own chromosomal DNA, and finally expresses the trait controlled by the incoming DNA.
• Since DNA is a hydrophilic molecule, it can not pass through membranes, so the bacterial cells must be made competent to take up DNA.
• This is done by treating them with a specific concentration of a divalent cation, such as calcium ($Ca^{2+}) which increases the efficiency with which DNA enters the bacterium through pores in its cell wall.

So, the correct answer is 'Increasing the efficiency with which DNA enters the bacterium through pores in its cell wall'.