Is/are used to cut dna at a specific nucleotide sequence.
a. gel electrophoresis
c. restriction enzymes
b. polymerase chain reactions
d. recombinant dna

Is there any solid scientific evidence that humans have been cloned?

Select the correct answer from each drop-down menu. the lac operon in e.coli regulates genes that code for enzymes required for breakdown of lactose. the lac operon is operon that is activated in the presence of .

Compare the shapes of the bones of the human skull with the shapes of the bones of the human leg. how do the shapes differ? why are the shapes important?