G. An explanation of the Genetic Code: DNA is a two-stranded molecule. Each strand is a polynucleotide composed of A (adenosine), T (thymidine), C (cytidine), and G (guanosine) residues polymerized by dehydration synthesis in linear chains with specific sequences.
Note: There are more than two types of epinephrine receptors on smooth muscle cells, so epinephrine may affect smooth muscle in other tissues in other ways. (There are subtypes of alpha and subtypes of beta.) * Details of how PLC generates IP3 are on handout 12A. We will go over this later.
a. Two basic types of epinephrine receptors -- called alpha and beta adrenergic receptors (adrenergic = for adrenaline). The two types are distinguished (primarily) by their relative affinities for epinephrine (adrenaline) and norepinephrine (noradrenaline).n example -- effects of epinephrine (adrenaline) on smooth muscle. Some smooth muscles relax, and some contract in response to epinephrine. In this case, different receptors & 2nd messengers are involved.