Question

question
which statement(s) describe(s) the autonomic nervous systems (anss)
neurotransmitters and their effects?
answer
all preganglionic autonomic fibers release ach at their
synaptic terminals, and their effects are stimulatory.
most postganglionic sympathetic terminals release the
neurotransmitter norepinephrine (ne), with usually a
stimulatory effect.
all of the listed responses are correct.
postganglionic parasympathetic fibers release ach, but
the effects may be either stimulatory or inhibitory,
depending on the nature of the receptor.
i dont know yet

Explanation:

• For the first option: All preganglionic autonomic fibers (both sympathetic and parasympathetic) release acetylcholine (ACh) at their synaptic terminals. The effects of ACh on the post - ganglionic neurons are generally stimulatory as they depolarize the post - ganglionic neurons to initiate an action potential.
• For the second option: Most postganglionic sympathetic terminals release norepinephrine (NE). NE usually has a stimulatory effect. For example, it can increase heart rate and contractility (stimulatory effect on the heart).
• For the fourth option: Postganglionic parasympathetic fibers release ACh. The effect of ACh on the target organ can be either stimulatory or inhibitory depending on the type of receptor. For example, ACh binding to muscarinic receptors in the heart (M2 receptors) is inhibitory (slows heart rate), while ACh binding to muscarinic receptors in the gastrointestinal tract (M3 receptors) is stimulatory (increases gastrointestinal motility).

Since all of the first, second, and fourth statements are correct, the “All of the listed responses are correct” option is also valid.

Answer:

All of the listed responses are correct.