Question

Enzyme(s) Bands observed (bp) 3000 3000 500, 2500 3000 A+B 250, 2750 A+C 250*, 2500 A +D 1250, 1750 A+C+D 250*. 1000. 1500 (note: * indicates very intense/bright bands) On the diagram below, construct a circular plasmid map of the plasmid consistent with the above data, showing: (i) The location of each enzyme cut site (11) The distances between the cut sites The single enzyme "B" cut site has been marked for you on the map at position "0" and marks have been placed at 500bp intervals around the 3000bp map to assist you. PUS Q2 Total size - 3 000 bp

Answer 1

ANSWER: Based on the data provided, the circular map of the plasmid construct is made where the location of each enzyme cut site is mentioned as well as the distances between the cut sites are also marked-

Explanation:

When the enzyme "A" is used, it cuts at location "2750bp" hence a linear fragment of 3000bp is obtained.

When enzyme "B" is used, it cuts at location "0bp" so a linear fragment of 3000bp is obtained.

When enzyme "C" is used it cuts at location "2500bp" and "0bp" and produced two linear fragments of 500bp and 2500bp.

When enzyme "D' is used it cuts at location "1500bp" at produced one single fragment of 3000bp.

When enzyme "A" and "B" are used in combination, "A" cuts at "2750bp" and "B" cut at "0bp" and two linear fragments were produced - 250bp and 2750bp.

When enzyme "A" and "C" are used in combination "A" cuts at "2750bp" and "C" cuts at two locations "0bp" and "2500bp" hence 3 fragments were produced- two 250bp fragments and one 2500bp.

When "A" and "D" are used in combination, "A" cuts at "2750bp" and "D" cuts at "1500bp" and two linear fragments were formed- 1250bp and 1750bp.

When "A",  "C" and "D" are used in combination, "A" cuts at "2750bp", "C" cut at two locations "0bp" and "2500bp" and "D" cuts at "1500bp", hence 4 linear fragments were formed, i.e. two 250bp fragments, one 1000bp and one 1500bp fragment.

Note: The enzyme "C" has two cut sites, one at 2500bp position and the 2nd one is overlapping the "B" enzyme's cut site, i.e. at 0bp(3000bp) location.

As a result of that when enzyme "C" is used in combination with "A" then it produced two 250bp (2500bp to 2750 bp & 2750bp to 3000bp) bands. That is why the intense band was observed for the 250bp fragment.