Question

Consider a piece of double-helical B-form DNA
that is 1000 base pairs (bp) long. In the
relaxed B-form, the rotation per base pair is 36
degrees (10 base pairs per turn).
The DNA starts off in a relaxed and open state.
Then, 4 turns of Z DNA are introduced into
the DNA by changing the salt conditions. The 4
turns are next to each other (i.e., they are
contiguous, as indicated in red in the diagram).
The Z-DNA segment is flanked by one turn of
unwound DNA (i.e., with no base pairs) on
either side. The DNA is then closed and the
ends are sealed without introducing further
turns.
What is the linking number of the closed
circular DNA? Explain.
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Answer 1

Answer:

DNA is genetic changes its a genes inside us