Biotechnology MCQs: Objective Questions with Answers

Edited By Irshad Anwar | Updated on Jul 02, 2025 05:29 PM IST

The term "biotechnology" describes the use of biology to solve issues and create useful products. The most well-known application of biotechnology is the creation of therapeutic proteins and other medications through genetic engineering.

It has applications in several fields, including agriculture and medicine. Biotechnology takes advantage of cellular and molecular processes to create goods and technologies that aid in better human and environmental well-being.

MCQs

1. The discovery of restriction enzymes was made by

Smith and Nathans
Alexander Fleming
Berg
None

2. By slicing apart viral DNA, bacteria defend themselves from viruses.

Ligase
Endonuclease
Exonuclease
Gyrase

3. The Klenow fragment comes from

DNA Ligase
DNA Pol-I
DNA Pol-II
Reverse Transcriptase

NEET Highest Scoring Chapters & Topics

Know Most Scoring Concepts in NEET 2024 Based on Previous Year Analysis.

Know More

4. ELISA test is

Using a second radiolabelled antibody
The use of RBCs
Using cell lysis caused by complement
Adding a material that transforms into a coloured final product

5. The Golden Rice variety contains a lot of

Vitamin C
Β-carotene and ferritin
Biotin
Lysine

6. The sticky ends of the DNA fragments are the result of

Endonuclease
Unpaired bases
Calcium ions
Free methylation

7. Which of the following justifies the use of plasmids as cloning vectors?

In culture, they can be multiplied
Bacterial cells that replicate themselves
Can be multiplied using enzymes in a laboratory
Freely replicate outside of bacterial cells

8. The year saw the beginning of the human genome project.

1980
1973
1990
1989

9. The vaccines prepared through recombinant DNA technology are

Third generation vaccines
First-generation vaccines
Second-generation vaccines
None

10. Which crop has undergone genetic modification?

Bt-cotton
Bt-brinjal
Golden rice
All

Also read

11. The PCR method was created by

Karry Mullis
Boyer
Sanger
Cohn

12. The initial transgenic plant that has been created is

Brinjal
Tobacco
Rice
Cotton

13. RNA interference facilitates

Cell proliferation
Micropropagation
Cell defense
Cell differentiation

14. Which of the following describes the enhanced transgenic basmati rice's quality?

A high yield is produced, but no distinctive aroma.
High output and high vitamin A content
Does not require growth hormones or chemical fertilisers
Able to fend off illnesses and insects

15. The first clinical use of gene therapy included a 4-year-old girl, for

Adenosine deaminase deficiency
Adenosine deficiency
Growth deficiency
Adenine deficiency

16. A gene's insertion and deletion are referred to as

Biotechnology
Genetic engineering
Cytogenetics
Gene therapy

17. A transgene's expression in the target tissue is detected using a

Transgene
Promoter
Enhancer
Reporter

18. ——- is a vector that is utilised to clone into higher organisms.

Retrovirus
Baculovirus
Salmonella typhimurium
Rhizopus nigricans

19. Which bacterium is used in the production of insulin by genetic engineering?

Saccharomyces
Rhizobium
Escherichia
Mycobacterium

20. Who Coined the Phrase "Biotechnology"?

National Center for Biotechnology Information (NCBI)
The European Federation of Biotechnology (EFB)
National Centre for Cell Science (NCCS)
National Institutes of Health (NIH)

21. Mention the two points of view that the term "biotechnology" encompasses.

Traditional biotechnology and Modern molecular biotechnology
Medical biotechnology and Agricultural biotechnology
Green biotechnology and Animal biotechnology
Blue biotechnology and Red biotechnology

22. The first recombinant DNA was produced using the bacterium ____'s plasmid.

Bacillus subtilis
Cyanobacteria
Salmonella typhimurium
Saccharomyces cerevisiae

23. The act of producing several copies of the desired DNA template is referred to as

Transferring
Cloning
Genetic engineering
R-DNA technology

24. The drawbacks of conventional hybridisation methods are overcome by _______ approaches.

Modern Hybridization
Immunology
Cell Biology
Genetic engineering

25. What are the two main methods that made contemporary biotechnology possible?

Classical and traditional biotechnology
Red biotechnology and green biotechnology
Genetic engineering and maintenance of a sterile environment
Genetics and mathematics

Answer Key

Smith and Nathans
Endonuclease
DNA Pol-I
Adding a material that transforms into a coloured final product
Β-carotene and ferritin
Unpaired bases
In culture, they can be multiplied
1990
Third generation vaccines
All
Karry Mullis
Tobacco
Cell defense
High output and high vitamin A content
Adenosine deaminase deficiency
Genetic engineering
Reporter
Retrovirus
Escherichia
The European Federation of Biotechnology (EFB)
Traditional biotechnology and Modern molecular biotechnology
Salmonella typhimurium
Cloning
Genetic engineering
Genetic engineering and maintenance of a sterile environment

Read More

Plasmid	biodiesel
Recombinant DNA Technology	Bt Cotton
Bioreactors	Transgenic Animals

Frequently Asked Questions (FAQs)

1. What is biotechnology and how does it differ from traditional biology?

Biotechnology is the use of biological systems, living organisms, or their derivatives to develop or create useful products and processes. Unlike traditional biology which focuses on studying living things, biotechnology applies biological knowledge to solve practical problems in areas like medicine, agriculture, and industry.

2. What are the key principles of genetic engineering in biotechnology?

The key principles of genetic engineering include: 1) Isolation of desired genes, 2) Insertion of genes into a suitable vector, 3) Transfer of the vector into a host organism, 4) Selection of transformed cells, and 5) Expression of the inserted genes in the host organism.

3. How does a restriction enzyme work in biotechnology applications?

Restriction enzymes are molecular scissors that cut DNA at specific sequences. They recognize particular DNA sequences (usually 4-8 base pairs long) and cleave the DNA at or near these sites. This allows scientists to cut DNA at precise locations, which is crucial for gene manipulation and cloning experiments.

4. What is the role of ligase in recombinant DNA technology?

DNA ligase is an enzyme that joins DNA fragments together by forming phosphodiester bonds between the 3' hydroxyl of one DNA fragment and the 5' phosphate of another. In recombinant DNA technology, ligase is used to join foreign DNA to vector DNA, creating recombinant DNA molecules.

5. How does a plasmid vector facilitate gene cloning?

Plasmid vectors are small, circular DNA molecules that can replicate independently in bacteria. They facilitate gene cloning by: 1) Carrying foreign DNA into host cells, 2) Replicating along with the host cell, thereby amplifying the inserted gene, 3) Often containing selectable markers for identifying transformed cells, and 4) Having multiple cloning sites for easy insertion of foreign DNA.

6. What is the difference between a genomic library and a cDNA library?

A genomic library contains DNA fragments representing an organism's entire genome, including both coding and non-coding regions. A cDNA library, on the other hand, contains only the coding sequences (exons) of expressed genes, as it's made from mRNA. cDNA libraries are useful for studying gene expression, while genomic libraries provide a complete picture of an organism's genetic makeup.

7. How does PCR (Polymerase Chain Reaction) amplify DNA?

PCR amplifies DNA through repeated cycles of: 1) Denaturation (separating DNA strands), 2) Annealing (binding of specific primers to target sequences), and 3) Extension (DNA synthesis by DNA polymerase). Each cycle doubles the amount of target DNA, resulting in exponential amplification.

8. What is the significance of selectable markers in genetic engineering?

Selectable markers are genes that confer a specific trait (e.g., antibiotic resistance) to transformed cells. They are crucial in genetic engineering because they allow scientists to identify and select cells that have successfully taken up foreign DNA, separating them from untransformed cells.

9. How does gel electrophoresis separate DNA fragments?

Gel electrophoresis separates DNA fragments based on their size. DNA, being negatively charged, moves through an agarose gel towards the positive electrode when an electric field is applied. Smaller fragments move faster through the gel matrix, while larger fragments move slower, resulting in separation.

10. What is the role of reverse transcriptase in creating cDNA libraries?

Reverse transcriptase is an enzyme that synthesizes DNA from an RNA template. In creating cDNA libraries, it's used to convert mRNA into complementary DNA (cDNA). This process allows scientists to study the expressed genes of an organism without the complications of introns and other non-coding sequences.

11. How does a bacterial artificial chromosome (BAC) differ from a plasmid vector?

BACs are larger than plasmid vectors and can carry DNA inserts of up to 300 kb, while plasmids typically carry inserts of 10 kb or less. BACs are based on the F-factor plasmid of E. coli and are useful for cloning large genomic fragments, making them valuable for genome mapping and sequencing projects.

12. What is the purpose of a promoter in a recombinant DNA construct?

A promoter is a DNA sequence that initiates gene transcription. In recombinant DNA constructs, promoters are used to control the expression of inserted genes. By choosing appropriate promoters, scientists can regulate when and where the inserted gene is expressed in the host organism.

13. How does Southern blotting differ from Northern blotting?

Southern blotting is used to detect specific DNA sequences, while Northern blotting detects specific RNA sequences. In Southern blotting, DNA is separated by gel electrophoresis and transferred to a membrane, whereas in Northern blotting, RNA is separated and transferred. Both techniques use labeled probes to detect specific sequences.

14. What is the significance of restriction fragment length polymorphism (RFLP) in biotechnology?

RFLP is a technique that exploits variations in homologous DNA sequences. It's significant in biotechnology for: 1) Genetic fingerprinting, 2) Mapping genomes, 3) Determining disease susceptibility, and 4) Studying genetic diversity and evolution. RFLPs are created by restriction enzymes and can be used as genetic markers.

15. How does a DNA microarray work and what is its application in biotechnology?

A DNA microarray is a collection of microscopic DNA spots attached to a solid surface. It works by hybridizing labeled DNA or RNA samples to these spots. Microarrays are used for large-scale gene expression studies, allowing researchers to monitor the expression levels of thousands of genes simultaneously, detect SNPs, and study gene regulation.

16. What is the principle behind DNA sequencing using the Sanger method?

The Sanger method, also known as chain-termination sequencing, involves DNA synthesis in the presence of normal deoxynucleotides (dNTPs) and modified nucleotides called dideoxynucleotides (ddNTPs). When a ddNTP is incorporated, it terminates DNA synthesis. By using different fluorescently labeled ddNTPs, researchers can determine the sequence of bases in a DNA fragment.

17. How does CRISPR-Cas9 technology work for gene editing?

CRISPR-Cas9 is a gene-editing tool that uses a guide RNA (gRNA) to direct the Cas9 enzyme to a specific DNA sequence. The Cas9 enzyme then cuts the DNA at this location. The cell's DNA repair mechanisms can then be exploited to either knock out the gene or insert a new DNA sequence, allowing precise genetic modifications.

18. What is the difference between transduction and transformation in bacterial gene transfer?

Transduction involves the transfer of genetic material between bacteria via a virus (bacteriophage), while transformation is the uptake of naked DNA from the environment by bacteria. In transduction, the phage acts as a vector carrying bacterial DNA, whereas in transformation, the bacteria directly incorporate external DNA into their genome.

19. How does RNA interference (RNAi) work to silence genes?

RNA interference is a biological process where small RNA molecules inhibit gene expression. It works through small interfering RNAs (siRNAs) or microRNAs (miRNAs) that bind to complementary mRNA sequences. This binding leads to the degradation of the target mRNA or prevents its translation, effectively "silencing" the gene.

20. What is the purpose of a reporter gene in biotechnology experiments?

A reporter gene is a gene that produces an easily detectable product when expressed. It's used to study gene expression, promoter activity, or the efficiency of gene transfer. Common reporter genes include those encoding fluorescent proteins (like GFP) or enzymes that produce colorimetric or luminescent products.

21. How does site-directed mutagenesis work and what is its application in protein engineering?

Site-directed mutagenesis is a technique used to make specific, intentional changes to DNA sequences. It typically involves using PCR with primers containing the desired mutation. This technique is crucial in protein engineering for studying protein function, improving enzyme activity, or altering protein properties for industrial or therapeutic applications.

22. What is the principle behind DNA fingerprinting and how is it used in forensics?

DNA fingerprinting is based on the unique patterns of repetitive DNA sequences (VNTRs or STRs) in an individual's genome. In forensics, DNA from a crime scene is extracted, amplified using PCR, and compared to DNA profiles of suspects or databases. The technique can identify individuals with high accuracy, making it valuable for solving crimes and establishing paternity.

23. How does a biosensor work and what are its applications in biotechnology?

A biosensor combines a biological component (like enzymes, antibodies, or nucleic acids) with a physicochemical detector. When the biological component interacts with a target molecule, the detector converts this interaction into a measurable signal. Biosensors are used in medical diagnostics, environmental monitoring, food safety testing, and drug discovery.

24. What is the difference between prokaryotic and eukaryotic gene expression systems in biotechnology?

Prokaryotic systems (like E. coli) are simpler, faster, and cheaper for protein production but lack post-translational modifications. Eukaryotic systems (like yeast or mammalian cells) are more complex but can perform proper folding and modifications of eukaryotic proteins. The choice depends on the protein's complexity and the desired application.

25. How does flow cytometry work and what is its significance in biotechnology?

Flow cytometry analyzes physical and chemical characteristics of particles in a fluid as they pass through a laser beam. It's significant in biotechnology for: 1) Cell sorting, 2) Analyzing cell populations, 3) Detecting specific proteins or DNA sequences, and 4) Studying cell cycle and apoptosis. It allows rapid analysis of large numbers of individual cells.

26. What is the principle behind enzyme-linked immunosorbent assay (ELISA) and its applications?

ELISA is a plate-based assay that detects and quantifies substances like peptides, proteins, antibodies, and hormones. It uses enzyme-linked antibodies to detect specific antigens. The enzyme converts a substrate into a detectable signal, usually a color change. ELISA is widely used in diagnostics, food safety testing, and research for detecting specific molecules with high sensitivity.

27. How does a DNA vaccine differ from a traditional vaccine?

A DNA vaccine contains genes encoding antigens, rather than the antigens themselves. When introduced into the body, cells take up the DNA and produce the antigen, stimulating an immune response. Traditional vaccines contain inactivated pathogens or their components. DNA vaccines can be safer, more stable, and easier to produce, but face challenges in delivery and efficacy.

28. What is the role of bioinformatics in modern biotechnology?

Bioinformatics combines biology, computer science, and data analysis to interpret biological data. It plays crucial roles in: 1) Analyzing genomic and proteomic data, 2) Predicting protein structures and functions, 3) Comparing genomes across species, 4) Designing drugs, and 5) Managing and interpreting large-scale biological experiments. It's essential for handling the vast amounts of data generated by modern biotechnology techniques.

29. How does protein engineering work and what are its applications?

Protein engineering involves modifying protein sequences to alter their structure and function. It can be done through rational design (using knowledge of protein structure) or directed evolution (random mutagenesis and selection). Applications include improving enzyme stability and activity, designing new proteins for industrial processes, and developing better therapeutics.

30. What is the principle behind phage display technology and how is it used in biotechnology?

Phage display involves inserting foreign DNA sequences into bacteriophage genes that code for surface proteins. This results in the foreign proteins being "displayed" on the phage surface. It's used for: 1) Studying protein-protein interactions, 2) Antibody engineering, 3) Peptide drug discovery, and 4) Selecting high-affinity binding molecules. It allows rapid screening of large libraries of proteins or peptides.

31. How does RNA sequencing (RNA-Seq) differ from DNA sequencing, and what unique information does it provide?

RNA-Seq involves sequencing cDNA derived from RNA samples, while DNA sequencing targets genomic DNA. RNA-Seq provides information on gene expression levels, alternative splicing events, and post-transcriptional modifications. It offers a snapshot of the transcriptome, revealing which genes are active in specific cells or conditions, crucial for understanding gene regulation and function.

32. What is metabolic engineering and how is it applied in biotechnology?

Metabolic engineering involves modifying metabolic pathways in organisms to enhance production of desired compounds or acquire new capabilities. It's applied in biotechnology to: 1) Increase yields of valuable metabolites, 2) Produce novel compounds, 3) Improve biofuel production, and 4) Enhance crop traits. It often involves gene addition, deletion, or regulation to optimize metabolic flux.

33. How does cell-free protein synthesis work and what are its advantages in biotechnology?

Cell-free protein synthesis occurs in vitro using cellular extracts containing the necessary machinery for transcription and translation. Advantages include: 1) Rapid protein production, 2) Ability to produce toxic proteins, 3) Easy modification of reaction conditions, and 4) Direct access to the reaction for adding or removing components. It's useful for protein engineering and studying difficult-to-express proteins.

34. What is the principle behind DNA barcoding and its applications in biodiversity studies?

DNA barcoding uses a short genetic marker in an organism's DNA to identify it as belonging to a particular species. It typically targets mitochondrial genes like COI. Applications include: 1) Identifying species, 2) Discovering new species, 3) Monitoring biodiversity, and 4) Detecting food fraud. It's particularly useful for identifying organisms that are difficult to distinguish morphologically.

35. How does optogenetics work and what is its significance in neuroscience research?

Optogenetics involves introducing light-sensitive proteins (opsins) into specific neurons. These neurons can then be activated or inhibited using light of specific wavelengths. It's significant in neuroscience for: 1) Studying neural circuits with high temporal and spatial precision, 2) Investigating brain function and behavior, and 3) Developing potential treatments for neurological disorders.

36. What is synthetic biology and how does it differ from traditional genetic engineering?

Synthetic biology involves designing and constructing new biological parts, devices, and systems, or redesigning existing natural biological systems for useful purposes. Unlike traditional genetic engineering, which typically involves transferring individual genes, synthetic biology often aims to create entire genetic circuits or even synthetic genomes. It applies engineering principles to biology, often using standardized genetic parts.

37. How does CRISPR interference (CRISPRi) differ from standard CRISPR-Cas9 gene editing?

CRISPRi uses a catalytically inactive Cas9 protein (dCas9) fused to a transcriptional repressor. Unlike standard CRISPR-Cas9 which cuts DNA, CRISPRi blocks transcription of target genes without modifying the DNA sequence. It's useful for studying gene function, as it allows reversible and tunable gene repression without permanent genetic changes.

38. What is the principle behind protein microarrays and their applications in biotechnology?

Protein microarrays consist of many different proteins attached to a solid surface in an ordered array. They work by detecting interactions between the immobilized proteins and other molecules in a sample. Applications include: 1) Studying protein-protein interactions, 2) Identifying enzyme substrates, 3) Detecting antibodies in patient samples, and 4) Drug discovery by screening for protein-drug interactions.

39. How does nanobiotechnology combine nanotechnology with biological systems?

Nanobiotechnology integrates nanoscale technology with biological systems and processes. It involves creating and using materials, devices, or systems at the molecular scale for biological applications. Examples include: 1) Nanoparticles for drug delivery, 2) Biosensors using nanostructures, 3) Nanofibers for tissue engineering, and 4) Nano-imaging techniques for studying cellular processes at unprecedented resolution.

40. What is the principle behind in vitro evolution techniques like ribosome display?

Ribosome display is an in vitro evolution technique that links proteins (phenotype) directly to their encoding mRNA (genotype) through stabilized ribosome complexes. It allows for the selection of proteins with desired properties from large libraries without the need for cell transformation. The technique is used for evolving proteins with improved or novel functions, particularly antibodies and enzymes.

41. How does genome editing using zinc finger nucleases (ZFNs) differ from CRISPR-Cas9?

ZFNs are engineered DNA-binding proteins fused to a DNA-cleaving enzyme. They recognize specific DNA sequences through zinc finger domains. Unlike CRISPR-Cas9, which uses RNA for targeting, ZFNs use protein-DNA recognition. ZFNs are more difficult to design and less versatile than CRIS