Recombinant DNA Applications Practice Questions
20 free Recombinant DNA Applications practice questions for the Zoology. Tap an option to answer — you get instant feedback, the correct answer, and a detailed explanation for every question.
Recombinant DNA technology primarily involves:
- A Natural mutation of genes
- B Combining DNA from different biological sources
- C Selective breeding of organisms
- D Protein synthesis without DNA involvement
Correct answer: Combining DNA from different biological sources
Recombinant DNA technology combines DNA fragments from different sources into a single molecule. This allows expression of desired genes in host organisms.
Which enzyme is essential for cutting DNA at specific nucleotide sequences?
- A DNA polymerase
- B RNA polymerase
- C Restriction endonuclease
- D DNA ligase
Correct answer: Restriction endonuclease
Restriction endonucleases recognize specific DNA sequences and cut them. They generate defined fragments required for recombinant DNA formation.
DNA ligase is used in recombinant DNA technology to:
- A Cut DNA fragments
- B Separate DNA strands
- C Join DNA fragments
- D Amplify DNA
Correct answer: Join DNA fragments
DNA ligase joins DNA fragments by forming phosphodiester bonds. It is essential for sealing inserted DNA into vectors.
Which molecule is commonly used as a vector in recombinant DNA experiments?
- A Ribosome
- B Plasmid
- C Chromosome
- D mRNA
Correct answer: Plasmid
Plasmids are small circular DNA molecules that can replicate independently. They are widely used as vectors to carry foreign genes.
The introduction of recombinant DNA into a host cell is called:
- A Transcription
- B Translation
- C Transformation
- D Replication
Correct answer: Transformation
Transformation refers to the uptake of recombinant DNA by host cells. It enables expression of the inserted gene.
Which host organism is most commonly used for recombinant DNA production?
- A Virus
- B Escherichia coli
- C Yeast
- D Plant cells
Correct answer: Escherichia coli
Escherichia coli is widely used due to its rapid growth and well-known genetics. It efficiently expresses recombinant genes.
Which technique is used to amplify a specific DNA segment?
- A Gel electrophoresis
- B Blotting
- C Polymerase chain reaction
- D Chromatography
Correct answer: Polymerase chain reaction
PCR amplifies specific DNA sequences exponentially. It allows production of millions of copies from a small DNA sample.
Which marker gene helps identify transformed host cells?
- A Housekeeping gene
- B Reporter gene
- C Structural gene
- D Operator gene
Correct answer: Reporter gene
Reporter genes produce detectable signals such as color or fluorescence. They help identify successful gene transfer.
Recombinant human insulin is produced using:
- A Animal pancreas
- B Plant tissues
- C Genetically engineered bacteria
- D Synthetic chemical methods
Correct answer: Genetically engineered bacteria
Human insulin is produced by inserting the insulin gene into bacteria. These bacteria synthesize insulin identical to the human form.
Which application of recombinant DNA technology is used in gene therapy?
- A Replacement of defective genes
- B Selective breeding of organisms
- C Protein purification only
- D Tissue transplantation
Correct answer: Replacement of defective genes
Gene therapy involves replacing or correcting defective genes. Recombinant DNA is used to deliver functional genes into patients.
Which step ensures expression of the foreign gene in the host?
- A Restriction digestion
- B Ligation
- C Use of suitable promoter
- D DNA isolation
Correct answer: Use of suitable promoter
A suitable promoter controls transcription of the inserted gene. It ensures efficient gene expression in the host cell.
Which organism is commonly used to produce recombinant vaccines?
- A Protozoa
- B Bacteria or yeast
- C Algae
- D Helminths
Correct answer: Bacteria or yeast
Bacteria and yeast are commonly used to produce recombinant vaccines. They are safe and efficient expression systems.
Gel electrophoresis is mainly used to:
- A Join DNA fragments
- B Amplify DNA
- C Separate DNA fragments by size
- D Sequence DNA
Correct answer: Separate DNA fragments by size
Gel electrophoresis separates DNA fragments based on size. Smaller fragments migrate faster through the gel.
Which application of recombinant DNA technology benefits agriculture?
- A Production of antibiotics
- B Development of transgenic crops
- C Blood group determination
- D Forensic analysis
Correct answer: Development of transgenic crops
Transgenic crops are developed using recombinant DNA technology. They show improved yield, resistance, or nutritional value.
Which enzyme synthesizes DNA from an RNA template?
- A DNA polymerase
- B RNA polymerase
- C Reverse transcriptase
- D Ligase
Correct answer: Reverse transcriptase
Reverse transcriptase synthesizes complementary DNA from RNA. It is essential for cloning eukaryotic genes.
cDNA differs from genomic DNA because it:
- A Contains introns
- B Lacks coding regions
- C Is synthesized from mRNA
- D Is double-stranded RNA
Correct answer: Is synthesized from mRNA
cDNA is synthesized from mature mRNA. It lacks introns and represents expressed genes.
Which biotech product is obtained using recombinant DNA technology?
- A Penicillin
- B Insulin
- C Vitamin C
- D Ethanol
Correct answer: Insulin
Insulin is produced using recombinant DNA technology. The human insulin gene is expressed in microbial hosts.
The role of selectable marker genes is to:
- A Increase gene expression
- B Identify non-transformed cells
- C Select transformed cells
- D Prevent DNA degradation
Correct answer: Select transformed cells
Selectable marker genes help identify cells that have taken up recombinant DNA. They confer survival advantage under selective conditions.
Which biosafety concern is associated with recombinant DNA technology?
- A Enhanced recombinant therapeutic protein yield
- B Uncontrolled spread of modified genes
- C Improved disease resistance
- D Cost-effective drug production
Correct answer: Uncontrolled spread of modified genes
A major concern is accidental release of genetically modified organisms. This may disrupt natural ecosystems.
Recombinant DNA technology has contributed most directly to:
- A Evolution of species over generations
- B Development of molecular diagnostics
- C Natural selection processes
- D Ecological succession
Correct answer: Development of molecular diagnostics
Recombinant DNA technology enables development of molecular diagnostics. It allows detection of genetic diseases and pathogens with high accuracy.