A student uses restriction enzymes to cut a DNA molecule into fragments. The digested DNA is loaded into the wells of an agarose gel and the gel is subjected to an electric current. Upon completion of the run, the gel is stained. Which of the following is true of the dye used to stain the fragments?
(A) It increases the contrast between the agar and the DNA fragments.
(B) It must be accounted for when calculating the molecular weight of the fragments.
(C) Its charged areas interfere with the migration of the DNA.
(D) It is bonded only to the sticky ends of the fragments and can directly determine
the sequence of the DNA fragments.
(E) It gives a three-dimensional view of the structure of the DNA fragments.
Answer: (A) It increases the contrast between the agar and the DNA fragments.
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The competitive inhibitor competes with the substrate for the ______ on the enzyme.
Fill in the blank(s) with the appropriate word(s).
_______ coping can allow people to step back from an especially overwhelming problem, which they can reassess later.
A. Problem-focused B. Primary-appraisal C. Secondary-appraisal D. Emotion-focused