Biotechnology MCQs set 2 for AKU Entry Test Biology — 20 solved questions.
Q1. A patient is diagnosed with a genetic disorder caused by a point mutation. Which biotechnology technique is used to detect this mutation?
Answer: DNA sequencing
Explanation: DNA sequencing detects the exact mutation, while PCR amplifies the DNA region; gene therapy treats the disorder.
Q2. A biotech company is developing a genetically modified crop resistant to a specific herbicide. What is the primary gene transfer method used?
Answer: Agrobacterium-mediated transformation
Explanation: Agrobacterium is commonly used for plant transformation; biolistics is also used but less common for herbicide resistance.
Q3. A scientist is studying the expression of a specific gene in a disease model. Which technique is best suited for quantifying mRNA levels?
Answer: RT-PCR
Explanation: RT-PCR quantifies mRNA; Western blotting detects proteins; Northern blotting is less sensitive than RT-PCR.
Q4. A genetic counselor is analyzing a family's pedigree to assess the risk of a genetic disorder. What biotechnology tool is used for this purpose?
Answer: Genetic linkage analysis
Explanation: Genetic linkage analysis identifies disease-linked genes; karyotyping detects chromosomal abnormalities.
Q5. A researcher is developing a vaccine using recombinant DNA technology. Which vector is commonly used for expressing the antigen?
Answer: Plasmid
Explanation: Plasmids are commonly used for antigen expression; bacteriophages and cosmids are used for cloning larger DNA fragments.
Q6. A patient is treated with a recombinant protein produced through biotechnology. Which disease is likely being treated if the protein is insulin?
Answer: Diabetes mellitus
Explanation: Insulin treats diabetes mellitus; growth hormone deficiency is treated with recombinant growth hormone.
Q7. A biologist is studying the function of a specific gene by analyzing its knockout in mice. What technique is used to create the knockout?
Answer: CRISPR-Cas9
Explanation: CRISPR-Cas9 is a precise gene editing tool; homologous recombination is used in traditional knockout methods.
Q8. A forensic scientist is analyzing DNA evidence from a crime scene. Which technique is used to amplify the DNA sample?
Answer: PCR
Explanation: PCR amplifies DNA; DNA sequencing determines the DNA sequence; DNA fingerprinting identifies individuals.
Q9. A company is producing a recombinant vaccine. What is the primary advantage of using a recombinant vaccine over a traditional vaccine?
Answer: Improved safety
Explanation: Recombinant vaccines are safer as they contain specific antigens; traditional vaccines may contain inactivated pathogens.
Q10. A researcher is using gel electrophoresis to separate DNA fragments. What is the basis for the separation?
Answer: Size
Explanation: Gel electrophoresis separates DNA by size; charge is a factor but size is the primary basis.
Q11. A genetic disorder is caused by a frameshift mutation. Which biotechnology technique can be used to correct this mutation?
Answer: Gene editing
Explanation: Gene editing corrects mutations; DNA sequencing detects mutations; PCR amplifies DNA regions.
Q12. A scientist is producing a recombinant protein in E. coli. What is the primary advantage of using E. coli as an expression system?
Answer: Low cost
Explanation: E. coli is a low-cost expression system; it lacks post-translational modifications found in eukaryotes.
Q13. A doctor is using genetic testing to diagnose a genetic disorder in a fetus. What is the primary source of fetal DNA for this test?
Answer: Amniotic fluid
Explanation: Amniotic fluid contains fetal cells; chorionic villus sampling is also used but involves placental tissue.
Q14. A researcher is studying the genetic basis of a disease using genome-wide association studies (GWAS). What is the primary goal of GWAS?
Answer: Identifying disease-causing genes
Explanation: GWAS identifies genetic variants associated with diseases; gene expression analysis is a separate technique.
Q15. A scientist is using RNA interference (RNAi) to study gene function. What is the mechanism by which RNAi silences gene expression?
Answer: Degrading mRNA
Explanation: RNAi degrades mRNA; it does not directly inhibit transcription or block translation.
Q16. A researcher is studying the effects of a specific gene knockout on development. Which model organism is commonly used for this purpose?
Answer: Mus musculus
Explanation: Mus musculus (mice) are commonly used for gene knockout studies due to their genetic similarity to humans.
Q17. A doctor is using genetic screening to identify carriers of a genetic disorder. What is the primary benefit of identifying carriers?
Answer: Preventing disease transmission
Explanation: Identifying carriers helps prevent disease transmission through genetic counseling and family planning.
Q18. A biologist is analyzing the phylogenetic relationship between different species using DNA sequences. What is the primary advantage of using DNA sequences for phylogenetic analysis?
Answer: High resolution
Explanation: DNA sequences provide high-resolution phylogenetic information; morphological and fossil data are also used but are less precise.
Q19. A scientist uses a restriction enzyme that cuts DNA at a palindrome sequence. What is unusual about the cut ends?
Answer: They are complementary and can reanneal
Explanation: Sticky ends are complementary and can reanneal; Not all palindromic cuts produce sticky ends, some are blunt.
Q20. Why is Taq polymerase used in PCR instead of human DNA polymerase?
Answer: It is thermostable
Explanation: Taq polymerase is thermostable, allowing it to withstand high PCR temperatures; Human DNA polymerase is not thermostable.