question_answer 24)

  Significance of heat shock method in bacterial transformation is to facilitate. (a) Binding of DNA to the cell wall (b) Uptake of DNA through membrane transport proteins (c) Uptake of DNA through transient pores in the bacterial cell wall (d) Expression of antibiotic resistance gene

Answer:

                  (c) In chemical method, the cell is treated with specific concentration of a divalent cation such as calcium to increase pore size in cell wall. The cells are incubated with recombinant DNA on ice, followed by placing them briefly at 42'-C and then putting it back on ice. This is called heat shock method. The bacteria now takes up there combinant DNA.