What state is the repressor protein in when tryptophan is absent?
a: the repressor protein is inactive
b: the repressor protein is active
c: the repressor protein is not expressed

Where can a dna be found in a prokaryotic cell

Math focus 4. calculate a map has index contours at 250 m, 500 m, and 750 m. what is the contour interval?

Which of the following may one conclude from a map that shows the average ph value of rainfall in the u.s.? acid rain is a more serious problem on the east coast. acid rain falls equivalently across the continental u.s. there are more factories on the west coast. the midwest has fewer forests than the rest of the u.s.