Biotechnology: Principles and Processes

Topics in this chapter

• Recombinant DNA and Gene Cloning
• DNA Isolation and Gel Analysis
• PCR and DNA Amplification
• Gene Libraries and Protein Expression
• Microbial Fermentation and Bioreactors

Cheat sheet

Practice questions

1. Question 1Q-71DED8

   A restriction enzyme recognises the sequence 5'-GAATTC-3' and cuts between G and A on both DNA strands. What type of ends are produced?

   1. A.Blunt ends with no single-stranded extension
   2. B.Sticky ends with a 5' single-stranded AATT overhang
   3. C.Sticky ends with a 3' single-stranded AATT overhang
   4. D.RNA-DNA hybrid ends
   See the answer and solution
2. Question 2Q-DD565D

   In an ideal polymerase chain reaction, one double-stranded DNA molecule is subjected to four complete cycles. Assuming complete duplication in every cycle, how many double-stranded DNA molecules will be present at the end?

   1. A.4
   2. B.8
   3. C.16
   4. D.32
   See the answer and solution
3. Question 3Q-AF5C32

   A foreign DNA fragment is inserted into the tetracycline-resistance gene of the plasmid pBR322, while the ampicillin-resistance gene remains functional. After transformation, which colony phenotype identifies recombinant bacteria?

   1. A.Growth on tetracycline but no growth on ampicillin
   2. B.Growth on ampicillin but no growth on tetracycline
   3. C.No growth on either ampicillin or tetracycline
   4. D.Growth on both ampicillin and tetracycline
   See the answer and solution
4. Question 4Q-D39CD8

   Which sequence correctly represents the major steps carried out after completion of microbial fermentation to obtain a purified biotechnology product?

   1. A.Transformation followed by restriction digestion and ligation
   2. B.Separation of the product, purification, and formulation
   3. C.Denaturation, annealing, and extension
   4. D.Replication, transcription, and translation
   See the answer and solution
5. Question 5Q-98216E

   During bacterial transformation, treatment of cells with calcium chloride followed by brief heat shock mainly helps to:

   1. A.Cut the plasmid DNA at specific recognition sites
   2. B.Increase the uptake of foreign DNA by bacterial cells
   3. C.Join the foreign DNA to the bacterial chromosome
   4. D.Replicate the plasmid outside the bacterial cell
   See the answer and solution