Question

Which of the following statements is FALSE?

		a. Binding of norepinephrine (NE) to an alpha-adrenergic receptor is usually excitatory, and binding to a beta-adrenergic receptor is usually inhibitory.
		b. The pulsatile secretion of hormones is needed to prevent receptor downregulation by target cells.
		c. A "pharmacological" dose refers to an abnormally high concentration of a substance—more than is normally present in the bloodstream.
		d. Autonomic motor nerves form synapses known as synapses en passant.
		e. A drug that blocks the action of a neurotransmitter is said to be an agonist of that neurotransmitter.
		f. Pheochromocytoma is a tumor of the adrenal medulla releasing large quantities of epinephrine and norepinephrine.

Answer 1

Answer:

Option E: A drug that blocks the action of a neurotransmitter is said to be an agonist of that neurotransmitter

Explanation: Neurotransmitters are the chemicals which are known to mediate their action by getting bound over the surface of their target which could be effectors muscle, or other nerve cells.

Also, agonists are the chemical substances which are known to promote the action of the neurotransmitters by getting bound to them over their surfaces. They thus are likely to promote the neuronal activity by enhancing the activity of the neurotransmitters. However, the antagonists are the chemicals which oppose the function of the neurotransmitters by blocking their pathway such that they remain inhibited from exhibiting their activity and expressions.

Thus, the chemicals which block the action mediated by the nuerotransmiiters are called as antagonist and not agonists.