Abase substitution that changes a codon coding for an amino acid to a stop codon is called a

In the context of the neural impulse, which of the following is true about the depolarization of neuron membranes?

When coal has reached it hardest, darkest form, it is called select one: 0 a. sub-bituminous b. lignite c. bituminous d. antrhacite next page

What causes darkening of the skin as melanin production increases