C. Energy that is the correct answer
The blob operon produces enzymes that convert compound A into compound B. The operon is controlled by regulatory gene S. Normally, the enzymes encoded by the operon are synthesized only in the absence of compound B. If gene S is mutated, the enzymes are synthesized in the both the presence AND absence of compound B. Gene S must encode a(n):
a. inducer.
A single gene disorder is one that's known to be caused by a single gene. Multiple gene disorders, however, can be caused by multiple gene combinations and other factors. Dominant genes are always expressed in the offspring, while recessive genes are only expressed if the offspring recieves the recessive gene from both parents. Sex-linked genetic disorders occur most often in men, and are caused by a single-gene disorder gene being on the X chromosome but not the Y, so that the offspring needs only one recessive gene to have the trait/disorder.
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