physiology extra stuff Flashcards
which mechanoreceptor is unencapsulated, large, slow adapting, type 1 and is located in the upper skin layers on areas with hair?
merkel’s discs
when a fiber is unencapsulated what does that do to its function?
unencapsulated allows for a sustained response
Merkel’s discs are unencapsulated
what is the function of Merkel’s discs?
pressure and texture
tactile sensation, light discriminate touch
allow finger tips to feel detailed surface patterns
what is the difference between type 1 and type 2 receptors?
type 1 have a small receptive field so they are more fine tuned
type 2 have large receptive fields with sustained response but less to do with perception; ruffini and stretch
which mechanoreceptor is fast adapting, encapsulated and located in highly sensitive areas like finger tips and lips?
meissner’s corpuscles
what is the function of meissner’s corpuscles?
tactile corpuscle, sensitive to shape and textural changes and discriminate touch as well as low frequency vibration
do not detect pain, only know that a stimulus is there
what is the difference between merkels and meissners
meissners detect changes in texture and vibration and are FAST
merkels detect sustained touch and pressure and are SLOW
what type of mechanoreceptor is deeper in the skin, encapsulated and slower; bulbous corpuscles?
ruffini endings
what is the function of ruffini endings?
detect tension deep in the skin- allow for grip or movement
thermoreceptor for warmth
proprioception and kinesthesia (movement awareness)
what type of mechanoreceptor is deeper in the skin, rapid and encapsulated?
pacinian corpuscles
what is the function of pacinian corpuscles?
high frequency vibration and pressure- detect surface structure (rough vs smooth)
deep pressure
what are bulboid corpuscle/krause end bulbs function?
thermoreceptors sensing cold
touch and pressure
which nociceptor is a myelinated fast responder with a small field for precise localized pain?
a-delta fibers
which nociceptor is unmyelinated, slow and with a large field for broad pain?
C fibers
which tract is responsible for pain and where is it located?
tract of lissauer
Rexed lamina I and II
what tract are merkel’s discs involved in?
anterior spinothalamic- light touch and pressure
what tracts are meissner’s involved with?
dorsal columns- gracilis and cuneatus
what area of the brain is responsible for speech production?
Broca’s area- Broadmann 44 and 45
what area is responsible for comprehension of spoken and written word?
Wernicke’s area- Broadmann 22
which broadmann area is the primary motor cortex?
4- origin of corticospinal tracts
what are broadmann areas 41 and 42?
primary auditory cortex
what is broadmann area 17?
primary visual cortex
what lobe is the primary somatosensory involved in spatial sense, proprioception, touch and language processing?
parietal lobe
which lobe contains the dopamine system involved in reward, attention, short term memory, planning and motivation?
frontal lobe
which lobe is responsible for retention of visual memory, language comprehension and emotion association?
temporal lobe
which steroid hormone acts as a growth hormone for reproductive organs, lining of vagina, important for maintaining oocytes on ovaries and also prevent apoptosis of sperm cells in males?
estradiol
what can estradiol be converted into in males?
testosterone
what is the most potent and prevalent endogenous estrogen, aka active estrogen?
estradiol
what are the differences in estradiol, estrone and estriol?
estradiol E1- strongest and active; present throughout
estrone E2-MENOPAUSE weaker, can be converted into estradiol-precursor; belly fat
estriol E3- placental estrogen, pregnancy
