16.4 - 16.6 (ANS)

How would the stimulation of muscarinic receptors in cardiac muscle affect the heart?

* Decreased heart rate explanation: Stimulation of muscarinic receptors, a type of cholinergic receptor located in postganglionic synapses of the parasympathetic nervous system, would cause K+ channels to open, resulting in hyperpolarization of the cardiac plasma membranes and a decreased heart rate.

what are the major effects produced by the parasympathetic division ?

* increased smooth muscle activity along the digestive tract * constriction of the respiratory passageway * secretion by digestive glands

Which of the following is NOT a region where parasympathetic preganglionic neurons are found? a) spinal cord segment s2 b) pons c) spinal cord segment t4 d) medulla oblongata

* spinal cord segment t4

Why are the effects of parasympathetic stimulation short lived?

Acetylcholine is quickly destroyed.

What is the name for a network of sympathetic and parasympathetic nerves that innervate organs in the thoracic and abdominopelvic cavities?

Autonomic plexus

What is the meaning of "dual innervation"?

Both the sympathetic and parasympathetic divisions stimulate the same organ.

Which of the following is NOT an effect of sympathetic stimulation? a) constriction of veins b) release of fats from adipose tissue c) increased heart rate d) constriction of airways

Constriction of airways

The autonomic nervous system performs which of the following functions?

Controlling respiratory functions during times of rest as well as times of activity

How would the stimulation of muscarinic receptors in cardiac muscle affect the heart?

Decreased heart rate

Which of the following is NOT an effect of parasympathetic stimulation?

Increased heart rate and blood pressure

Why is autonomic tone important to autonomic motor neurons?

It allows for an increase or decrease of activity, thus providing a greater amount of control.

Which of the following is not a function of the parasympathetic nervous system?

Mobilization of energy reserves through the accelerated breakdown of glycogen in muscle and liver cells and the release of lipids by adipose tissues

What are the receptors found at neuroglandular junctions in the parasympathetic division?

Muscarinic receptors explanation: Muscarinic receptors occur at cholinergic neuromuscular and neuroglandular junctions in the parasympathetic division. They can also be found at a few cholinergic junctions in the sympathetic division. Muscarinic receptors are G protein-coupled receptors. Their stimulation and G protein activation produces excitatory or inhibitory responses, depending on the activation or inactivation of specific enzymes. The enzyme activation causes changes in membrane permeability to K+.

What are the receptors that are found on all ganglionic cells of both the sympathetic and parasympathetic divisions of the ANS?

Nicotinic receptors

What are the nerves that carry sacral parasympathetic output to the bladder, terminal parts of the large intestine, and the sex organs?

Pelvic nerves

what are the autonomic plexus and ganglia

Plexus: -cardiac plexus - pulmonary plexus - esophageal plexus - celiac plexus - hypogastric plexus - inferior mesenteric plexus ganglia:

Which nerve is responsible for parasympathetic innervation of the lungs, heart, stomach, liver, pancreas, and parts of the small and large intestine?

The vagus nerve

The major effects produced by the parasympathetic division include which of the following? a) secretion by digestive glands b) constriction of the respiratory passageway c) increased smooth muscle activity along the digestive tract

all of the listed responses are correct

The effects produced by sympathetic postganglionic fibers in spinal nerves include which of the following?

all of the listed responses are correct - acceleration of blood flow to skeletal muscles - dilation of the pupil and focusing of the eyes - stimulation of secretion by sweat glands

The effects of parasympathetic stimulation are usually

brief in duration and restricted to specific organs and sites

The effects of parasympathetic stimulation are usually __________.

brief in duration and restricted to specific organs and sites

The effects of parasympathetic stimulation are usually

brief in duration and restricted to specific organs and sites explanation: The effects of parasympathetic stimulation are usually brief in duration and restricted to specific organs and sites. The signals are brief in duration because of the faster rate at which acetylcholine is broken down in the synapses. The acetylcholine is broken down within seconds by the enzyme acetylcholinesterase; this is in contrast to the duration of sympathetic effects, which may last for several minutes. Effects long in duration and diverse in distribution are characteristic of the SNS.

Parasympathetic preganglionic fibers of the vagus nerve entering the abdominopelvic cavity join the __________.

celiac plexus

Intramural ganglia are components of the parasympathetic division that are located __________.

inside the tissues of visceral organs

What is the term for parasympathetic ganglia that are embedded in the tissues of the target organ?

intramural ganglia

In the parasympathetic division, postganglionic neurons originate in _________

intramural ganglia or ganglia associated with the target organs

In organs that receive dual innervation from the sympathetic and the parasympathetic divisions, the two divisions produce

opposing effects

In organs that receive dual innervation from the sympathetic and the parasympathetic divisions, the two divisions produce __________.

opposing effects

Which division of the autonomic nervous system (ANS) innervates only visceral structures serviced by the cranial nerves or by the nerves lying within the abdominopelvic cavity?

parasympathetic division

Why is the parasympathetic division sometimes referred to as the anabolic system?

parasympathetic stimulation causes an increase in nutrients content in the blood.

The neurotransmitter released by all parasympathetic neurons is __________.

so the neurotransmitter that released by ALL parasympathetic neurons is (ACh) - acetylcholine. so the acetylcholine is released at the pre-ganglionic fibers and post-gangglionic fibers to produce effect on the target organs. * epinephrine and nor epinephrine are released by post-ganglionic sympathetic neurons