One way that regulation is often studied is by examining the effects of mutations. For example, mutations within the parts of the lac operon have been well studied. Which of these mutants would be considered a constitutive mutant?A. a mutation in the promoter for the operon
B. a mutation in the gene for β-galactosidase
C. a mutation in the gene for the repressor
D. a mutation in the gene for β-galactosidase permease

Select the correct answer from each drop-down menu proteins are

Female luna moths (actias luna) attract males by emitting chemical signals that spread through the air. a male hundreds of meters away can detect these molecules and fly toward their source. the sensory organs responsible for this behavior are the comblike antennae visible in the photograph shown here. each filament of an antenna is equipped with thousands of receptor cells that detect the sex attractant. based on what you learned in this chapter, propose a hypothesis to account for the ability of the male moth to detect a specific molecule in the presence of many other molecules in the air. what predictions does your hypothesis make? design an experiment to test one of these predictions.

Which diagram best represents the chromosomes that would be found in a two new skin cells produced as a result of this process?