Concept:DNA fragments are generated, separated, and visualised using specific molecular biology techniques.
Key Fact:Restriction enzymes cut DNA at specific sites, creating fragments.
Gel electrophoresis separates these fragments based on size.
Visualisation requires staining and exposure to UV light.
Explanation:Statement A is correct: Restriction enzymes are called molecular scissors because they cut DNA precisely.
Statement B is correct: During agarose gel electrophoresis, DNA fragments move through the gel; smaller fragments travel faster and separate from larger ones.
Statement C is incorrect: Separated DNA fragments are not visible without staining; they must first be stained with ethidium bromide.
Statement D is incorrect: Ethidium bromide‑stained DNA is only visible when the gel is exposed to UV light; it does not fluoresce in visible light.
Thus, only statements A and B are correct.
Answer:Option B – A and B only.
