Question 1

Alpha and beta receptors are the two primary subcategories of&#10;A) muscarinic cholinergic receptors&#10;B) nicotinic cholinergic receptors&#10;C) dopamine receptors&#10;D) 5-hydroxytryptamine (serotonin)&#10;E) adrenergic

Accepted Answer

Alpha and beta receptors are subtypes of adrenergic receptors, which are activated by adrenaline and noradrenaline. This classification is based on the specific binding affinity of the receptors for different agonists and their respective downstream signaling pathways.

Question 2

A drug that affects nicotinic cholinergic receptors will affect activity in both divisions of the autonomic nervous system (ANS)because&#10;A) nicotinic cholinergic receptors are found on all organs and tissues innervated by the ANS&#10;B) nicotinic cholinergic receptors are located at the junction between preganglionic and postganglionic neurons in both the sympathetic and parasympathetic pathways&#10;C) both divisions of the ANS affect peripheral tissues by releasing epinephrine onto those tissues&#10;D) all the above are true&#10;E) none of the above are true

Accepted Answer

Nicotinic cholinergic receptors are located at the junction between preganglionic and postganglionic neurons in both the sympathetic and parasympathetic pathways. Therefore, a drug that affects these receptors will affect activity in both divisions of the autonomic nervous system. Option A is not accurate because not all organs and tissues innervated by the ANS have nicotinic cholinergic receptors. Option C is not accurate because while both divisions of the ANS can mediate the release of epinephrine, it is not the sole mechanism by which they affect peripheral tissues. Option D is incorrect because only option B is accurate.

Question 3

All preganglionic neurons and parasympathetic postganglionic neurons are said to be _____ in nature because of the presence of ______ at their respective synapses.&#10;A) adrenergic; norepinephrine&#10;B) cholinergic; norepinephrine&#10;C) adrenergic; acetylcholine&#10;D) cholinergic; acetylcholine&#10;E) adrenergic; epinephrine

Accepted Answer

Preganglionic neurons and parasympathetic postganglionic neurons are cholinergic in nature because they release acetylcholine at their respective synapses. Adrenergic neurons release norepinephrine or epinephrine as their neurotransmitter. Therefore, options A, B, C, and E are incorrect.

Question 4

In most peripheral tissues,sympathetic postganglionic neurons release ____ that binds directly to ____ receptors.&#10;A) epinephrine; adrenergic&#10;B) epinephrine; cholinergic&#10;C) norepinephrine; adrenergic&#10;D) norepinephrine; cholinergic&#10;E) acetylcholine; adrenergic

Accepted Answer

Sympathetic postganglionic neurons release norepinephrine that binds directly to adrenergic receptors in most peripheral tissues.

Question 5

A drug that inhibits muscarinic cholinergic receptors will selectively&#10;A) increase sympathetic responses on peripheral tissues&#10;B) decrease sympathetic responses on peripheral tissues&#10;C) increase parasympathetic responses on peripheral tissues&#10;D) decrease parasympathetic responses on peripheral tissues&#10;E) increase responses in all tissues innervated by the autonomic nervous system

Accepted Answer

Muscarinic cholinergic receptors are primarily found on tissues innervated by the parasympathetic nervous system, so inhibiting these receptors will lead to a decrease in parasympathetic responses on peripheral tissues.

Deck 18: Introduction to Autonomic Pharmacology