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. The rate of migration of the DNA fragments through the agarose gel is determined by the
(A) ratio of adenine to cytosine in the fragment
(B) presence of hydrogen bonds between base pairs
(C) length of time the electrophoresis unit is allowed to operate
(D) number of nucleotides in the fragment
(E) volume of the starting sample
Ans: (D) number of nucleotides in the fragment
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What is the function of a statolith?
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Crops that are resistant to the herbicide Roundup ____
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If a child has an AB blood type, the parents
a. must both have different blood types. b. must be A and B, but not AB. c. must both be AB. d. can be any blood type. e. can have different blood types, but neither can be blood type O.
The sequence of nitrogen-containing bases on one strand of DNA could determine all of the following EXCEPT the sequence of
A) nitrogen-containing bases in mRNA. B) nitrogen-containing bases in the other DNA strand. C) ribose and phosphate molecules in tRNA. D) amino acids in a protein molecule.