Heat Shock

Q. Significance of heat shock method in bacterial transformation is to facilitate

1. binding of DNA to the cell wall
2. uptake of DNA through membrane transport proteins
3. uptake of DNA through transient pores in the bacterial cell wall
4. expression of antibiotic resistance gene

Q. Significance of treating bacterial cells with calcium chloride before transformation is to facilitate

1. binding of DNA to the cell surface
2. uptake of DNA through membrane transport proteins
3. uptake of DNA by creating transient pores in the bacterial cell wall
4. expression of antibiotic resistance gene

Q. Choose the correct sequence of steps involved in the process of making bacterial cells competent before transformation:
I. Heat shock at ${42}^o$C
II. Place on ice
III. Treat bacterial cells with a compound containing divalent cation
IV. Incubate bacterial cells with rDNA

1. IV → I → III → II → I
2. III → II → IV → I → II
3. III → IV → II → I → II
4. IV → II → III → I → II

Q. Heat shock is used in biotechnology for:

1. DNA extraction
2. Tissue culture
3. Creating transient pores in cell membrane
4. Somaclone preparation

Q. What is the role of Calcium Chloride in the heat shock method of transformation?

1. It give positive charge to the cell wall
2. It creates the pores of the cell membrane
3. It help the DNA to move into the cell
4. All of the above

Q. What is the role of Calcium Chloride in the heat shock method of transformation?

1. It give positive charge to the cell wall
2. It creates the pores of the cell membrane
3. It help the DNA to move into the cell
4. All of the above

Q. Significance of heat shock method in bacterial transformation is to facilitate

1. binding of DNA to the cell wall
2. uptake of DNA through membrane transport proteins
3. uptake of DNA through transient pores in the bacterial cell wall
4. expression of antibiotic resistance gene

Q. Calculate the approximate number of unit cells present in 1g of Au. When Au crystallizes in FCC lattice (Au=197)

Q. Give reasons for the following:
DNA always moves towards anode during gel-electrophoresis.

Q. The term "competent" refers to

1. Increasing the competition between cells
2. Making cells impermeable for DNA
3. Increasing the efficiency with which DNA enters the bacterium through pores in its cell wall
4. Making cells permeable for divalent cations

Q. Significance of the ‘heat shock’ in bacterial transformation is to facilitate