Identify the location where norepinephrine will be acting directly via beta2 receptor bindin
a. enteric activation of smooth muscle contraction in duodenum
b. parasympathetic post -ganglionic activation of pancreatic enryme secretion
c. sympathetic post-ganglionic activation of the bronchioles
d. sa node
e. muscles

Feedback mechanisms regulate the rate of enzyme activity, effectively "turning off' an enzyme in a reversible way until more product is needed. which of the following would be most effective as a feedback mechanism? a. reduced concentration of product b. increased concentration of substrate c. a change in ph d. temporary binding of a non-substrate molecule in the active site