Plasmids are pieces of DNA that contain recognition sites where restriction enzymes cut plasmid.
To separate and find out the length of fragments cut by restriction enzymes, scientist use a technique called gel electrophoresis. During gel electrophoresis, fragments with smaller size move faster while those with bigger size move slower.
A connected circle with 'x' number of recognition sites gets broken into 'x' pieces while a linear strand with 'x' number of recognition sites gets broken into 'x-1' pieces.
With different combinations of restriction enzymes in different lanes, and assuming that everything runs smoothly, there are no overlapping bands, and so on:
- The length totals for each lane must…
- The number of bands in a multi-enzyme lane (such as A+B) must …
- The longest fragment in a multi-enzyme lane cannot be …
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