Unit 3: Autonomic Nervous System

Somatic Nervous System, Autonomic Nervous System

What are the 2 systems involved with Motor Division?

Somatic Nervous System

involved with voluntary control of specific bodily functions.

skeletal muscle

What are the effectors of SNS?

Autonomic Nervous System

the subset of the motor division responsible for self regulated bodily functions. Is self regulating and functions independent of the will.

Cardiac muscle, Smooth muscle, Endocrine glands, Exocrine glands

What are the effectors of the ANS?

number of neurons involved in both systems

What is the anatomical difference between ANS and SNS from the somatic innervation of skeletal muscles?

1

How many motor neurons are involved the Somatic pathway?

2

How many neurons are involved in the Autonomic pathway?

ganglion

Where do the 2 neurons meet and form a synapse?

preganglionic neuron

A neuron that has its cell body in the CNS and courses to the autonomic ganglion.

post ganglionic neuron

A neuron that has its cell body in the autonomic ganglion and carries the impulse from that ganglion to the effector.

Sympathetic, Parasympathetic

What are the system divisions of the ANS?

Sympathetic

Associated with "fight or flight" responses

Parasympathetic

Associated with "rest and digest" functions.

T1-T12, L1-L2/L3

What does the Sympathetic system involve regarding spinal cord segments?

Thoracolumbar

What is the anatomical term for the Sympathetic system?

near the spinal cord

Where are the sympathetic ganglia are located?

sympathetic chain ganglia

Resemble a string of pearls as they course alone either side of the vertebral bodies.

short preganglionic, long postganglionic

What are the lengths of the preganglionic and postganglionic fibers in sympathetic system?

Sympathetic

Any physiological function that involves increased heart rate, respiration, or alertness.

Unit action

Sympathetic stimulation activates many organs at one time.

CN III, VII, IX, X; S2, S3, S4

What does the Parasympathetic system involve?

Cranio-sacral

What is the anatomical term for the Parasympathetic system?

ciliary muscles, Pupillary constrictor muscles

What does CN III (Oculomotor) provide parasympathetic innervation to?

lens accommodation for close vision

What do ciliary muscles do?

pupil constriction

What do pupillary constrictor muscles do?

lacrimal glands, submandibular and sublingual salivary glands

What does CN VII (Facial) provide parasympathetic innervation to?

release of tears

What do lacrimal glands do?

production of saliva, anterior 2/3 of tongue for taste

What do the submandibular and sublingual salivary glands do?

parotid salivary glands

What does CN IX (Glossopharyngeal) provide parasympathetic innervation to?

saliva production

What do the parotid salivary glands do?

Thoracic organs, most abdominal organs, thorax

What does CN X (Vagus) provide parasympathetic innervation to?

decreased diameter of airways and heart rate

What does the thorax do?

increased peristalsis, secretory activity of digestive organs

What does the abdomen do?

distal portions of large intestine, rectum, urinary bladder, reproductive organs

What do S2, S3, S4 provide parasympathetic innervation to?

near/within wall innervated organ

Where are parasympathetic ganglia located?

long preganglionic, short postganglionic

What are the lengths of the preganglionic and postganglionic fibers in parasympathetic?

1

How many organs does the parasympathetic system stimulus involve at a time?

Parasympathetic

Physiological functions involving digestion, sexual stimulation or decreased alertness.

sympathetic

stimulates dilator muscles which dilate the pupil of the eye. This allows more light into the eye and improves peripheral vision.

parasympathetic

stimulates constrictor muscles which constrict the pupil of the eye. It also changes the lens accommodation which allows us to focus on close up objects.

sympathetic

inhibits secretory activity of all glands having to do with digestion and causes vasoconstriction of the blood vessels supplying these glands (thus decreasing their blood supply).

parasympathetic

increases secretory activity of digestive glands thus facilitating digestion.

sympathetic

stimulates copious sweating. This serves (in part) to reduce body heat in response to increased metabolic activity

parasympathetic

has little to no effect on sweat gland production or secretion.

sympathetic

stimulates arrector pilorum muscles to contract causing vellus hair to stand erect (goosebumps).

parasympathetic

has little to no effect on arrector pilorum muscles

sympathetic

increases the rate and force of the heartbeat.

Sympathetic Chain ganglion

Where is sympathetic innervation of the heart derived from?

Either side of spinal column

Where is the Sympathetic Chain ganglion located?

Norepinepherine

The release of this neurotransmitter directly to the myocardium of the ventricles will result in increased heart rate.

parasympathetic

decreases the force of heart contraction and slows the heart rate.

CN X (Vagus)

What is parasympathetic innervation of the heart supplied by?

Achetylcholine

Release of this neurotransmitter at the SA node will act to decrease the rate and intensity of myocardial contractions thus, slowing the heart rate.

sympathetic

decreases the activity of glands and muscles of the digestive system. It also constricts sphincters of the digestive tract preventing the passage of food and feces.

parasympathetic

increases motility (peristalsis) and the amount of secretion by accessory digestive organs. It also relaxes sphincters to allow movement of food along the tract.

sympathetic

constricts most blood vessels associated with the skin and abdominal viscera and increases blood pressure. Causes vasodilation of the blood vessels that supply skeletal muscles, the brain and sensory organs.

parasympathetic

constricts blood flow to the skeletal muscles and brain thus decreasing alertness. Also causes vasodilation of the blood vessels that supply abdominal viscera; therefor increasing blood flow to the digestive tract and reproductive organs (leading to an erection)

sympathetic

increases alertness and mental activity by increasing blood flow to the brain and increasing metabolic activity.

parasympathetic

slightly decreases mental activity as it redirects blood flow to the digestive and reproductive systems

sympathetic

involved in the excitatory process of orgasm and ejaculation during sexual intercourse.

parasympathetic

involved with the vasodilation of the blood vessels of the male and female genitalia. Increased blood flow results in erections of the penis and clitoris during sexual stimulation.