Molecular Biology MCQ – MCQ on CRISPR
1. What does the cas9 protein do?
- Prevents viruses from entering bacteria
- Cut RNA
- Cut DNA
- Binds to RNA
[expand title=”Show Answer”]Answer: Cut DNA
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2. How does the guide RNA help the cell know where to cut the DNA?
- Guide RNA helps to find the PAM
- Guide RNA is complementary to the DNA sequence
- Guide RNA always binds to the same sequence of DNA
- Like restriction sites, they are always palindromes
[expand title=”Show Answer”]Answer: Guide RNA is complementary to the DNA sequence
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3. What is the role of the guide RNA?
- It helps the cell repair the DNA
- ensures that the Cas9 enzyme cuts at the right point in the genome
- Recognizes PAM sequences and opens up the DNA
- makes a cut across both strands of the DNA
[expand title=”Show Answer”]Answer: ensures that the Cas9 enzyme cuts at the right point in the genome
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4. A PAM is
- a 15-20 bp sequence snipped from a viral genome that serves as a tracer DNA to locate viruses later
- a 3 bp sequence that adjacent to viral DNA in a CRISPR array
- a girl’s name popular in the 1960s
- where the DNA is cut
[expand title=”Show Answer”]Answer: a 3 bp sequence that adjacent to viral DNA in a CRISPR array
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5. Why do bacteria have CRISPR? Check all that apply.
- To be able to remember which viruses they have been infected with
- To be able to edit virus DNA
- To cut apart virus DNA thereby stopping the virus infection
- To be able to edit their own DNA
[expand title=”Show Answer”]Answer:
To be able to remember which viruses they have been infected with,
To cut apart virus DNA thereby stopping the virus infection
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6. CRISPR can edit DNA. What organisms naturally has CRISPR?
- Viruses
- Humans
- Plants
- Bacteria
[expand title=”Show Answer”]Answer:
Bacteria
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7. What does the acronym CRISPR stand for?
- Controlled Reservative Image Spectacle Palindromic Recounts
- Clustered Regularly-Interspaced Short Palindromic Repeats
[expand title=”Show Answer”]Answer:
Clustered Regularly-Interspaced Short Palindromic Repeats
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8. CRISPR-Cas9 is a type of __ system found in bacteria
- digestive
- endocrine
- circulatory
- immune
[expand title=”Show Answer”]Answer:
immune
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9. CRISPR-Cas9 was discovered in which of the following organisms?
- protists
- fungi
- bacteria
- viruses
[expand title=”Show Answer”]Answer:
bacteria
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10. Scientists have adapted it to turn it into a biotechnology tool for _ DNA.
- building
- editing
- destroying
- synthesizing
[expand title=”Show Answer”]Answer:
editing
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11. The enzyme portion of this process is called __.
- CRISPR
- Replicase
- Lysozyme
- Cas9
[expand title=”Show Answer”]Answer:
Cas9
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12. What type of RNA is used as a GPS of sorts, to find or locate specific genes?
- mRNA
- gRNA
- tRNA
- rRNA
[expand title=”Show Answer”]Answer:
gRNA
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13. What is PAM?
- a 3 letter sequence for binding on the target DNA
- the main gene portion of the DNA
- the cut site for Cas9
- a 10 letter sequence for binding on the target DNA
[expand title=”Show Answer”]Answer:
a 3 letter sequence for binding on the target DNA
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14. After Cas9 cuts the target DNA, cellular enzymes attempt to repair the break. Which of the following types of repair mechanisms creates a mutation and inactivates the gene.
- Homology-Directed Repair (HDR edited DNA strand)
- Non-Homologous End Joining (NHEJ random DNA)
[expand title=”Show Answer”]Answer:
Non-Homologous End Joining (NHEJ random DNA)
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15. After Cas9 cuts the target DNA, cellular enzymes attempt to repair the break. Which of the following repair mechanisms involves “editing” of the gene with insertion of a corrected sequence?
- Homology-Directed Repair (HDR edited DNA strand)
- Non-Homologous End Joining (NHEJ random DNA)
[expand title=”Show Answer”]Answer:
Homology-Directed Repair (HDR edited DNA strand)
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16. What is one of the enzymes produced by the CRISPR system?
- Cas – 9
- Cas – 8
- Cas – 7
- Cas – 5
[expand title=”Show Answer”]Answer:
Cas – 9
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17. What is a Gene?
- A segment of RNA that encodes for a protein
- A chromosome
- A segment of DNA that encodes for a protein
- Your genome
[expand title=”Show Answer”]Answer:
A segment of DNA that encodes for a protein
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18. In order for offspring to get a genetic mutation, the mutation must occur in what type of cell?
- Cells with no nucleus.
- Any body cell after birth.
- Cells with no cell wall or cell membrane.
- Cells like eggs or sperm cells that are undergoing reproduction.
[expand title=”Show Answer”]Answer:
Cells like eggs or sperm cells that are undergoing reproduction.
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19. What is the correct order of steps in the CRISPR process?
- targeting, binding, cleaving, repairing
- targeting, repairing, binding, cleaving
- binding, targeting, repairing, cleaving,
- targeting, cleaving, repairing, binding
[expand title=”Show Answer”]Answer:
targeting, binding, cleaving, repairing
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