chapter 16 - autonomic nervous system

branch of NS that controls skeletal muscle

somatic nervous system

branch of NS that controls smooth muscle, cardiac muscle, and glands

autonomic nervous system

controls cardiac and smooth muscle, controls glandular tissue, associated with involuntary responses

autonomic nervous system

regulates involuntary body functions; heart rate, digestion, respiratory rate, pupillary response, glandular secretion

autonomic nervous system

autonomic nervous system operates through __ involving visceral sensory and motor neurons

reflex arcs

fight or flight

sympathetic

rest and digest

parasympathetic nervous system

controls digestive function

enteric nervous system

T or F: each target effector (visceral organ) has DUAL innervation between sympathetic and parasympathetic division

true

prepares the body for stressful or emergency situations; many effector organs are activated together

sympathetic division

increased heart rate, pupil dilation, reduced digestive activity, release of glucose, bronchodilation

effects of sympathetic divsion

originate in thoracolumbar spinal cord lateral gray horns

preganglionic neurons

found in the sympathetic nervous system; thoracolumbar spinal cord t1-l2 lateral gray horns is referred to as

thoracolumbar division

modified sympathetic ganglion that releases epinephrine/norepinephrine into blood

adrenal medulla

prevertebral, near major abdominal arteries

collateral ganglia

paravertebral, alongside the spinal cord

sympathetic chain ganglia

shunts blood to skeletal muscles and heart, dilates bronchioles, liver release glucose

during vigorous physical activity

promotes relaxation, energy conservation, and maintenance of homeostasis

parasympathetic division

increased digestive activity, salivation, decreased heart rate, stimulation of urination, pupil constriction, bronchoconstriction

effects of parasympathetic division

in the parasympathetic division, preganglionic neurons arise from? referred to as?

brainstem and sacral spinal cord; craniosacral division (sacral spinal cord segments)

what cranial nerves in craniosacral division carry fibers

oculomotor, facial, glossopharyngeal, vagus

synapse near or within target organs/effector

terminal ganglia

embedded in the GI tract; contains sensory neurons, interneurons, and motor neurons; regulates digestive functions such as peristalsis

enteric nervous system

parasympathetic division ; sympathetic division _ the enteric nervous system

stimulates, inhibits

regulates involuntary functions such as blood pressure, digestion, and body temp.

autonomic reflexes

autonomic reflexes operate through ___ involving sensory receptors, integration centers, and autonomic motor outputs

visceral reflex arcs

maintains ___ by adjusting organ function in response to internal changes (autonomic reflexes)

homeostasis

detects change in internal environment (baroreceptors in blood vessels)

sensory receptor

visceral sensory neurons carry signals to CNS

afferent pathway

usually in the hypothalamus or brainstem; processes input and determines response

integration center

autonomic motor neurons (sympathetic or parasympathetic) carry output to effectors

efferent pathway

smooth muscle, cardiac muscle, or gland that changes activity to restore balance

effector

involve smooth muscle, cardiac muscle, or glands

visceral reflexes

involve skeletal muscles

somatic reflexes

pain from visceral organs perceived at body surface; due to shared spinal cord pathways; heart pain felt in left arm

referred pain

maintains stable blood pressure via heart rate and vessel diameter adjustments

baroreceptor reflex

regulates pupil size to control light entry into the eye

pupillary light reflex

controls bladder emptying

micturition reflex

medulla and pons integrate cardiovascular, respiratory, and digestive reflexes

brainstem

coordinates reflexes such as urination, defecation, and sexual function

spinal cord

ex/ body temperature, blood glucose; maintained through negative feedback loops

set points

work together to maintain stable internal conditions

sympathetic and parasympathetic systems; homeostatic regulation

light stimulates nerve conductance of action potentials down optic nerve to the brain

pupillary reflex

sympathetic output __ pupil in low light

dilates

light to one eye triggers a ___ response in both pupils

bilateral response

T or F: if the pupillary reflex is not working it can signify more severe brain trauma in the brain or brain stem

true

can check ___ and ____ to see if someone is unconscious

optic and oculomotor

sympathetic stimulation dilates pupil; eye has best chance at vision during fight or flight, allows max light in pupil

mydriasis

parasympathetic stimulation constricts pupil; reduces amount of light needing to enter as you should be relaxing

miosis

acts as the master control center of autonomic and endocrine regulation; helps with regulating and maintaining homeostasis

hypothalamus

drop in blood pressure upon standing due to delayed baroreceptor response

orthostatic hypotension