quiz questions Flashcards
During a fast contraction, recruitment threshold for motor units will be lower or decrease compared to a slower contraction.
True
False
true
During a voluntary contraction, alpha-gamma co-activation keeps the muscle spindles activated. Why is this important?
to maintain spindle sensitivity during a shortening contraction
In heathy young adults, type I motor units will have larger axon diameters and have fewer muscle fibers than type IIb/X motor units
false - type II have larger - improves ocnduction velocity
Type II motor neurons innervate fast glycolytic type muscle fibers and type I motor neurons innervate _______________.
slow oxidative type MF
0 / 1 point
Which neurotoxin prevents the release of acetylcholine into the neuromuscular junction
botox
roll, pitch, yaw - match each tot he semicircular canals
yaw-horizontal
roll - posterior
pitch - anterior
head rotaion causes endolymph to move in the ____ direction
opposite direction
which neurotoxin preevents release of ach intp the NMJ
release = botox (botulinum toxin)
orde rhte muscle fibres form lowest to highest glycolytic enzymes
type I, type IIa, type IIb/x
type 1 motor neurons hvae a ____ fiametere and ___ activation t heshold
small, low
Autogenic inhibition activates the Ib afferents and in turn inhibits the antagonist motor neurons.
True
Correct answer:
False
false - inhibits the agonist
The inhibition of the agonist motor neurons, and subsequently decrease in force is called __________.
autogenic inhibtiion
Astronauts on the international space station live in a zero-gravity environment. Which of the following vestibular end organs would be affected by a change in gravity? (Choose all that apply)
Utricle/sacule
when the sterocilia are directd aay form kinocilium the vestibular afferent is ____ causin ___ in firing rates
hyperpoalrzied, decreases
oint receptors code ambiguously for joint movements.
True
False
true
During a seated position, looking straight forward, primary vestibular afferents innervating the mechanoreceptors of the semi-circular canals will have no background activity. True or false
false - leacky cahnnels in vestibular afferents - provide backgrounda ctivity
When rotating your head quickly to the left, the left semi-circular canal vestibular afferents will _________; whereas the right vestibular afferents will ___________. (Choose the correct answers)
depolatize (excitation), hyperpolaize (inh9ibiitio)
endolymph si rich in what chemical improtan for neural function?
potassium
Cutaneous mechanoreceptors are innervated by afferents that have larger axon diameters than muscle spindle afferents.true or false
false
The _______ is described as the spatial extent of the receptor surface from which the sensory neuron receives input.
receptive field
Ménière’s Disease typically occurs due to _______________ endolymphatic pressure in the semicircular canals, causing ______________ firing rates on the affected side.
increase, decrase
Simple neural receptors have nerve endings enclosed in connective tissue capsules. true or false?
false
After ingesting too much alcohol, why do some people experience “the spins”?
Alcohol thins the blood, disrupting the density in the semi-circular canals.
In her computer chair, five-year old version of Lisa is sitting and spinning around to her left with her nose pointing downward towards the floor. Which vestibular end organs will likely detect her angular movement? (Choose the correct answer)
post canal
How does the Epley Maneuver work to reduce dizziness associated with BPPV?
consecutive head mototion allow otolitchic crystal to be directed out of semiciruclat canal reducing dizziness
