What is the superhelical density (sigma) of a closed-circular DNA with Lk₀ = 200 and Lk = 190?
Explanation
Superhelical density (σ) is a measure of the degree of supercoiling that is independent of the DNA molecule's length. It's calculated by dividing the change in linking number (ΔLk) by the linking number of the relaxed molecule (Lk₀).
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