1. What does CRISPR stand for?
a) Clusters of Repetitive Interspaced Palindromic Sequences
b) Clusters of Regulated Introns and Specific Palindromes
c) Cross-linked Introns and Specific Probes
d) Chromosomal Repeated Introns in Specific Palindromes
Answer: a) Clusters of Repetitive Interspaced Palindromic Sequences
2. What is the primary function of CRISPR in bacteria?
a) Repairing DNA damage
b) Storing genetic information
c) Defending against viruses
d) Synthesizing proteins
Answer: c) Defending against viruses
3. Which protein is most commonly associated with the CRISPR gene-editing system?
a) Cas9
b) RNA polymerase
c) DNA ligase
d) Helicase
Answer: a) Cas9
4. What is the role of Cas9 in the CRISPR system?
a) To cut the target DNA at specific locations
b) To replicate the DNA
c) To transcribe RNA
d) To store genetic information
Answer: a) To cut the target DNA at specific locations
5. What is a guide RNA in the CRISPR system?
a) A molecule that helps in DNA repair
b) A molecule that directs Cas9 to the correct DNA sequence
c) A protein that activates gene expression
d) A DNA molecule that encodes the Cas9 protein
Answer: b) A molecule that directs Cas9 to the correct DNA sequence
6. Which of the following organisms have been modified using CRISPR gene editing?
a) Bacteria
b) Mice
c) Plants
d) All of the above
Answer: d) All of the above
7. What is the main advantage of using CRISPR over previous gene-editing techniques like TALENs and ZFNs?
a) CRISPR is cheaper and more efficient
b) CRISPR works only on plants
c) CRISPR does not require guide RNA
d) CRISPR is less specific
Answer: a) CRISPR is cheaper and more efficient
8. Which disease was one of the first targets for CRISPR gene-editing research in humans?
a) Sickle cell anemia
b) Down syndrome
c) Alzheimer’s disease
d) Cancer
Answer: a) Sickle cell anemia
9. What happens after Cas9 cuts the DNA?
a) The cell repairs the break by inserting a new gene
b) The DNA break is naturally repaired by the cell’s repair mechanisms
c) The cell dies immediately
d) The DNA break is ignored by the cell
Answer: b) The DNA break is naturally repaired by the cell’s repair mechanisms
10. Which type of DNA repair mechanism is most commonly used after a CRISPR cut?
a) Non-homologous end joining (NHEJ)
b) Homologous recombination
c) DNA replication
d) Apoptosis
Answer: a) Non-homologous end joining (NHEJ)
11. Which of the following is a potential ethical concern regarding CRISPR gene editing?
a) Its potential to cure genetic diseases
b) Its ability to modify germline cells, leading to inheritable changes
c) Its widespread use in agriculture
d) Its application only in laboratory research
Answer: b) Its ability to modify germline cells, leading to inheritable changes
12. Which of these is a potential application of CRISPR in agriculture?
a) Creating genetically modified crops that are resistant to pests
b) Enhancing the nutritional value of crops
c) Making animals disease-resistant
d) All of the above
Answer: d) All of the above
13. What is gene drive technology in relation to CRISPR?
a) A method to delete unwanted genes from the genome
b) A technique to force a particular gene to spread rapidly through a population
c) A way to enhance the expression of beneficial genes
d) A way to clone organisms with specific traits
Answer: b) A technique to force a particular gene to spread rapidly through a population
14. What was the first successful use of CRISPR in human embryos?
a) To correct genetic defects causing Duchenne muscular dystrophy
b) To create genetically modified embryos resistant to HIV
c) To edit the gene responsible for beta-thalassemia
d) To enhance intelligence in embryos
Answer: c) To edit the gene responsible for beta-thalassemia
15. Which of the following is an example of a disease that might be treated using CRISPR gene editing?
a) Huntington’s disease
b) Cystic fibrosis
c) Muscular dystrophy
d) All of the above
Answer: d) All of the above
16. Which type of cell can be directly edited using CRISPR to treat genetic disorders?
a) Somatic cells
b) Germline cells
c) Stem cells
d) All of the above
Answer: d) All of the above
17. What is one of the limitations of CRISPR technology?
a) Its inability to target specific genes
b) Its inability to cut DNA at all
c) The risk of off-target mutations
d) It only works in plant cells
Answer: c) The risk of off-target mutations
18. Which molecule is used to guide Cas9 to the target DNA sequence?
a) mRNA
b) tRNA
c) Guide RNA (gRNA)
d) Ribosomal RNA (rRNA)
Answer: c) Guide RNA (gRNA)
19. What was the key discovery by Jennifer Doudna and Emmanuelle Charpentier in 2012?
a) The discovery of the CRISPR gene-editing system
b) The isolation of the Cas9 protein
c) The first human gene therapy using CRISPR
d) The use of CRISPR for cloning mammals
Answer: a) The discovery of the CRISPR gene-editing system
20. How does CRISPR improve gene editing over older technologies like TALENs and ZFNs?
a) CRISPR requires fewer proteins
b) CRISPR can target multiple genes at once
c) CRISPR is cheaper and more efficient
d) All of the above
Answer: d) All of the above
21. What is a potential benefit of CRISPR gene editing in medicine?
a) Permanent changes in the genetic code of human beings
b) Treatment of genetic disorders by correcting mutations
c) Creation of designer babies
d) Inhibition of gene expression in adult cells
Answer: b) Treatment of genetic disorders by correcting mutations
22. Which organism has been genetically modified using CRISPR to resist malaria?
a) Mice
b) Mosquitoes
c) Cows
d) Chickens
Answer: b) Mosquitoes
23. What is the primary challenge in using CRISPR to edit the human germline?
a) Ethical concerns and the possibility of unintended genetic changes
b) Difficulty in isolating human DNA
c) CRISPR can only be used on somatic cells
d) CRISPR is ineffective in humans
Answer: a) Ethical concerns and the possibility of unintended genetic changes
24. Which of the following is a key application of CRISPR in agriculture?
a) Improving crop yield and disease resistance
b) Cloning animals for food production
c) Creating new species of plants
d) Altering the nutritional content of meats
Answer: a) Improving crop yield and disease resistance
25. What is the role of “off-target effects” in CRISPR gene editing?
a) Off-target effects lead to the desired genetic change
b) Off-target effects cause unintended DNA changes at locations other than the target site
c) Off-target effects enhance gene expression
d) Off-target effects are irrelevant in gene editing
Answer: b) Off-target effects cause unintended DNA changes at locations other than the target site
26. Which molecule guides Cas9 to its target site in the DNA?
a) Guide RNA (gRNA)
b) Messenger RNA (mRNA)
c) Transfer RNA (tRNA)
d) Ribosomal RNA (rRNA)
Answer: a) Guide RNA (gRNA)
27. What is one of the risks associated with using CRISPR in gene therapy?
a) Immune rejection of edited cells
b) The inability to target the correct gene
c) Loss of genetic diversity in populations
d) Lack of effective targeting in plants
Answer: a) Immune rejection of edited cells
28. What is the potential of CRISPR for curing genetic diseases?
a) It can permanently cure genetic disorders by correcting mutations
b) It can only alleviate symptoms but not cure diseases
c) It can only be used for curing cancers
d) It cannot be used for genetic diseases
Answer: a) It can permanently cure genetic disorders by correcting mutations
29. Which of these is a limitation of CRISPR in human gene editing?
a) Difficulty in editing non-coding regions of DNA
b) Lack of specificity in targeting genes
c) Only works on animal cells
d) It cannot target multiple genes at once
Answer: b) Lack of specificity in targeting genes
30. Which of the following is an example of CRISPR’s application in human health?
a) Treatment of HIV by editing immune cells
b) Creating genetically modified animals for organ donation
c) Curing Alzheimer’s disease through gene editing
d) All of the above
Answer: a) Treatment of HIV by editing immune cells
These MCQs cover a wide range of topics related to CRISPR and gene editing, providing a broad understanding of its potential and challenges.
