Question

CRISPR is a modern technology used for precise DNA editing.
(a) Explain the role of the following in this technology:
• Guide RNA
• Cas9 enzyme

Hint:

Remember: Guide RNA = GPS (finds the location), Cas9 = scissors (cuts the DNA). Together they enable precise gene editing.

Answer 1

Step 1: Understand CRISPR technology.
CRISPR-Cas9 is a gene-editing tool that allows scientists to cut and modify DNA at specific locations. It works like molecular scissors guided to a target sequence.
Step 2: Role of Guide RNA (gRNA).
Guide RNA is responsible for identifying and binding to the specific DNA sequence that needs to be edited. It has a sequence complementary to the target DNA, ensuring high precision in locating the correct site.
Step 3: Function of Guide RNA.
Once bound, the guide RNA directs the Cas9 enzyme exactly to the target site on the DNA, acting like a navigator.
Step 4: Role of Cas9 enzyme.
Cas9 is an endonuclease enzyme that acts as molecular scissors. It cuts the DNA strands at the specific location identified by the guide RNA.
Step 5: Final outcome of the process.
After the DNA is cut, the cell's natural repair mechanisms allow scientists to insert, delete, or modify genes, enabling precise genetic editing.