The noncoding regions of a primary mRNA transcript that interrupt coding regions are known as:

The noncoding regions of a primary mRNA transcript that interrupt coding regions are known as:
 
  A. exons.
  B. introns.
  C. poly(A) tails.
  D. 5' caps.

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Which of the following is a correct pairing of RecBCD subunit to its activity?
 
  A. RecB  5'-3' helicase
  B. RecD  nuclease
  C. RecD  3'-5' helicase
  D. RecB  chi binding
  E. RecC  has a pin structure that helps separate strands.

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The effector molecule for the Trp repressor of the trp operon is:
 
  A. tyrosine.
  B. lactose.
  C. arabinose.
  D. tryptophan.

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A temperature sensitive mutant of Sp1 is isolated. When cells are grown at the permissive temperature, cell function appears normal. However, at high temperatures, the phenotypic effect of this mutation would most likely be:
 
  A. reduced transcription.
  B. increased transcription.
  C. reduced levels of H1.
  D. increased levels of H1.
  E. problems with DNA packaging.

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The effector for the Lac repressor protein is:
 
  A. lactose.
  B. allolactose.
  C. glucose.
  D. -galactosidase.