lab 7: autonomic, nervous system 2 Flashcards
functions of the autonomic nervous system
- regulated functions of internal organs, such as heart, stomach and intestines
- part of the PNS, controls some muscles within body
autonomic NS vs. somatic NS function
- ANS controls involuntary actions (beating heart, perspiration)
- SNS controls voluntary actions via nerve impulses from the PNS
2 subdivisions of the autonomic NS
- sympathetic (during exertion, stress or emergency)
parasympathetic (resting conditions)
how many neurons involved in efferent autonomic NS
2 - preganglionic and postganglionic
general function of the parasym. and sym. NS
sympathetic - fight or flight, increase HR, BP, breathing, vasodilation, decrease digestion
parasympathetic - rest and digest, increase nutrient uptake, decrease HR breathing, metabolism
location of preganglionic neurons in parasympathetic NS
brain stem, lateral portion of anterior gray horn S2-S4
location of preganglionic neurons in sympathetic NS
lateral gray horns of spinal segments from T1-L2
location of PNS ganglia in parasympathetic NS
terminal
location of PNS ganglia in sympathetic NS
intramural (terminal for nose, eyes and salivary glands)
preganglionic fibres of sympathetic NS
myelinated, short, release Ach
preganglionic fibres of parasympathetic NS
myelinated, long, release Ach
postganglionic fibres of parasympathetic NS
unmyelinated, short, release Ach
postganglionic fibres of sympathetic NS
unmyelinated, long, release norepinephrine
why is the sympathetic NS also called thoracolumbar division
nerves exit spinal cord from thoracic and lumbar regions (T1-L2)
what type of fibres of the sympathetic ANS travel through white rami communicantes
myelinated preganglionic fibers
where are the sympathetic chain ganglia found?
in the ventral roots of spinal nerves T1-L2
what type of nerve fibers travel through the gray rami communicantes
unmyelinated postganglionic fibers
what are the visceral effector organs innervated by the sympathetic ANS in the thoracic cavity?
heart and lungs
what is inside the collateral ganglia?
cerebrospinal fluid
what visceral effector organs in the abdominopelvic cavity are innervated by the sympathetic ANS?
liver, gallbladder, stomach, spleen, pancreas, large and small intestine, sex organs, excretory organs
what effect does sympathetic stimulation have on the visceral effector organs
inhibits blood flow to organs, decrease activity to abdominopelvic cavity
why is the parasympathetic NS also known as the craniosacral division?
nerves exit the spinal cord through the brain stem and sacral region
cranial nerve III innervates
eye, tears
cranial nerve VII innervates
salivary gland, tears
cranial nerve IX innervates
salivary gland, tears
cranial nerve X innervates
heart, liver, lungs, gallbladder, spleen, stomach, long and short intestines
what is a nerve plexus
bundles of nerves
what level does the sacral section of the parasympathetic division exit the spinal cord
S2-S4
4 organs innervated by the sacral parasympathetic neurons
uterus, ovary, penis, scrotum, urinary bladder, kidney, rectum
what are ventricles?
fluid filled cavities within the brain that are filled with cerebrospinal fluid
functions of cerebrospinal fluid
- prevents contact between brain and surrounding bones
- supports the brain
- transports nutrients, chemical messengers and waste products
2 layers of the dura mater
endosteal layer and meningeal layer
what are the dural sinuses
between the endosteal and meningeal layer, filled with interstitial fluid and blood vessels
what flows in the subarachnoid space?
cerebrospinal fluid
what is the pia mater?
highly vascular membrane that acts as a floor to support the large central blood vessels as they branch over the brain
white matter contains
myelinated axons
gray matter contains
nerve cell bodies, glial cells, and unmyelinated axons
frontal lobe function
conscious control of skeletal muscles
temporal lobe function
conscious perception of auditory and olfactory stimuli
parietal lobe function
conscious perception of touch, press, vibration, pain, temperature and taste
occipital lobe function
conscious perception of visual stimuli
prefrontal cortex function
perform complicated learning and reasoning functions, provides emotional context and motivation, producing future consequences of events
insula lobe function
language and balance, visceral functions (upset stomach, full bladder), some aspects of smell
precentral gyrus function
primary motor cortex; voluntary movement by controlling somatic motor neurons
postcentral gyrus function
primary sensory cortex; receive somatic sensory info from touch, pressure, pain, taste and temp receptors from dorsal columns and spinothalamic tracts
corpus callosum function
composed of central white matter and links the right and left hemispheres
thalamus function
- relay center for sensory and motor pathways
- ## filters info for sensory actions
hypothalamus function
Sex drives, hunger and appetite, autonomic function
Little bit emotional and endocrine
midbrain function
-process visual and auditory info and generates responses to the stimuli
pons function
involved with involuntary control of respiration
cerebellum function
- planning, execution, and coordination of limb and trunk movements
- maintenance of balance and control of eye movements
- motor movements such as posture, balance, coordination and speech
medulla oblongata function
helps regulate breathing, heart and blood vessel function, digestion, sneezing and swallowing
2 types of nerves
cranial nerves and spinal nerves
