Question

Which of these is NOT a method to make host cells ' competent ' to take up DNA ?

• A. Use of disarmed pathogen vectors
• B. Micro-injection
• C. Elution
• D. Biolistics

Answer 1

The Correct Option is C

• Methods to make cells competent include use of disarmed pathogen vectors, micro-injection, and biolistics, all of which involve manipulating cells to enhance their ability to take up DNA.
• Elution does not relate to making cells competent for DNA uptake, as it is a method used in purification processes, not genetic transformation.

The correct answer is (C) : Elution.

Answer 2

The correct answer is: (C) Elution.

Making host cells "competent" refers to the process of preparing them to take up foreign DNA, such as plasmids or genes, from their environment. This is an essential step in molecular biology techniques like transformation and transfection. Several methods are used to make cells competent, but elution is not one of them.

Common methods to make cells competent include:

• Calcium chloride treatment: One of the most widely used methods where cells are exposed to calcium chloride, making their membranes more permeable to DNA.
• Electroporation: A method where an electric field is applied to cells to create temporary pores in the membrane, allowing DNA to enter.
• Heat shock: In this method, cells are subjected to a sudden increase in temperature, which helps DNA to enter through the pores in the membrane.

Elution, on the other hand, refers to the process of washing or removing substances, such as DNA, from a column or other medium, and is not a method for making cells competent to take up DNA.

Therefore, Elution is the correct answer, as it is not related to making host cells competent.