Autonomic Nervous System Flashcards
What do both the ANS and SNS respond to stimulus from?
The sensory nervous system
What type of system is the SNS and ANS
Motor Systems
How many axons does the SNS use to travel from the spinal cord to a skeletal muscle fiber
1
How many axons does the ANS use to travel from the spinal cord to smooth muscle, cardiac, or a gland?
2
How do axons in the ANS communicate with each other?
Via ganglia (one labeled pre-ganglionic, the other post-ganglionic)
The axons in the SNS are only…
excitatory
The axons in the ANS are
both excitatory and inhibitory
Where is the soma of preganglionic neurons found? (ANS)
brain/spinal cord
Where is the autonomic ganglia found?
PNS
What does the parasympathetic division of the ANS do?
Conserves energy and replenishes nutrient storage (homeostasis)
What does the sympathetic division do?
Increases alertness and metabolic activity (fight or flight)
Parasympathetic Division
Preganglionic axon is very long coming from the soma to the ganglion and is myelinated
The ganglia are close to the terminal ganglion (target) or found in the walls of the target (intermural ganglion)
Second axon is nonmyelinated
What is the parasympathetic division also known as?
The craniosacral division
Where are the somas of the parasympathetic nervous system?
Sacrum and cranium
Which cranial nerves have autonomic fibers running with them?
Oculomotor (CN III) (extintric muscles of eye)
Facial (CN VII) (lacrimal gland/submandibular/sublingual gland)
Glossopharyngeal (CN IX)
Vagus (CN X)(interal organs in anterior cavity)
Sympathetic Division
Short, myelinated preganglionic axon. Synapse in the sympathetic trunk ganglia (lateral to the spinal cord). Referred to as white rami
Postganglionic axon is referred to as grey rami (can both be referred to as grey/white rami communicates)
What is the sympathetic nervous system also known as?
Thoracolumbar division
(one stimulus can activate all neurons up and down the trunk)
What system activates the adrenal medulla?
Sympathetic Nervous System. Releases epinephrine and norepinephrine.
What neurotransmitter does the sympathetic and parasympathetic release?
Aceteylcholine (excitatory effect)
What receptors do preganglionic neurons have?
Nicotinic
What receptors do parasympathetic target cells have?
Muscarinic
What receptors do sympathetic axons which stimulate blood vessels and sweat glands have?
Acetylcholine to muscarinic.
What do all other sympathetic ganglionic axons release
Norepinephrine to adrenergic
Generally, which system stimulates smooth/cardiac muscle and glands
Both parasympathetic and sympathetic (dual innervation). Mainly work as antagonists to each other
What system stimulates ventricles of the heart to increase force
Only sympathetic
What system stimulates the adrenal medulla to release epinephrine and norepinephrine
Only sympathetic
what system stimulates the penis to create an errection?
Only parasympathetic nervous system
What does the pupil do?
Lets light into the eye to be converted into electrical signals.
What does the iris do?
Controls how much light is let into your pupil (size)
What does the sclera do?
Maintains your eye shape and protects
What does the caruncle do?
Produces a dense secretion
What does the upper and lower eyelid do?
Protective covering for the eye shielding from outside objects
What is the trochlea of the eye?
Where the trochlear nerve goes to innervate the superior oblique muscle
What is the vitreous gel?
transparent, colorless, gel-like substance that fills the space between the lens and the retina within the eye
What is the anterior chamber of the eye?
aqueous humor -filled space inside the eye between the iris and the cornea ‘s innermost surface, the endothelium.
What is the cornea of the eye?
transparent front part of the eye that refracts light and accounts for two-thirds of the eye’s optical power
What does the lens do?
Curved disc that bends and focuses light to help you see images clearly
What is the ciliary body/muscle do?
Changes the shape of the lens
What does the retina do?
Receives light that lens has focused and converted into neural signs
What does the macula do?
Lets you focus on small detail for when light hits
What does the fovea do?
Lets you focus on sharpest detail (small depression in lens)
What does the conjunctiva do?
It covers the inside of the eyelid and the white of the eye (sclera), preventing foreign bodies and infections.
Produces mucus and tears: It helps lubricate the eye and contributes to immune surveillance.
Keeps the eye moist: It allows the eyelid to move smoothly and protects the eye from dust and debris.
What does the episclera do?
Layer of clear tissue that covers the sclera
What does the malleus do?
Bone that transmits info from eardrum to inner ear
What does the incus do?
Transmits vibrations
What does the stapes do?
Creates wave of fluid that turn sound into electrical energy
What do the semicircular canals do?
Regulate balance in your body- they have fluid in them
What does the cochlea do?
Converts nerve impulses to sound
What does the tympanic membrane do?
, thin layer of tissue in the human ear that receives sound vibrations from the outer air and transmits them to the auditory ossicles
What does the eustachian tube do?
Draining fluid from the middle ear
Protecting the middle ear from viruses and bacteria
Equalizing the pressure around the ear drums (which is why you hear your ears pop after swallowing or yawning)
What is the ressiner’s membrane?
separates the cochlear duct from the vestibular duct. It helps to transmit vibrations from fluid in the vestibular duct to the cochlear duct.
What is the scala media?
an endolymph filled cavity inside the cochlea, located between the tympanic duct and the vestibular duct, separated by the basilar membrane and the vestibular membrane (
What is the scala vestibuli
a perilymph-filled cavity inside the cochlea of the inner ear that conducts sound vibrations to the cochlear duct.
It is separated from the cochlear duct by Reissner’s membrane and extends from the vestibule of the ear to the helicotrema where it joins the tympanic duct.
What is the tectorial membrane?
highly hydrated extracellular matrix that resides above the hair bundles of mechanosensory hair cells in the cochlea
What is the origin of Corti?
