WEEK 1: Neurophysio [Doc Dee lecture vid] Flashcards
based on the nernst equation the equilibrium potential is primarily influenced by
concentration gradient
the nernst potential is the potential insdie/outside the membrane
inside
negativity of the RMP is primarily determined by? secondarily by?
K permeability
sodium (secondarily)
all the cells of the body has RMP T or F
T
what causes the RMP?
unequal distribution of uncharged particles
predominant ions in the ECF?
sodium and chloride
predominant ions in the ICF
potassium
ratio of sodium ions from inside to outside?
1 is to 10
ratio of potassium from inside to outside
35 to 1
the membrane is more permeable to sodium/potassium?
potassium. 100 x as great
sodium influx is greatest during this phase of the action potential of a neuron
depolarization
stages of action potential?
DORA! depolarization overshoot (reversal of polarity) repolarization (returning to RMP) After hyperpolarization (more negative than the RMP)
lowest intensity of a stimulus that will trigger an action potential
threshold stimulus
least intensity that will elicit the highest visible response?
maximal stimulus
increasing the stimulus above threshold levels does not cause the devt of larger action potential. T or F
T
absolute refractory period is from where to where in the action potential?
depolarization to 2/3 of the repolarization
the direction of impulse conduction if a stimulus is applied at the middle of the axon is
bidirectionally pero walang action potential na magaganap
increading the diameter of the axon will lead to increase/decrease of the impulse transmission?
increase. because when you increase the diameter of the axon -> decrease axoplasmic resistance -> increased space constant
what is the charge of sodium? chloride?
sodium is positive, chloride is negative
2 subthreshold stimuli applied at the same time resulted to a visible response. the property of synpase exhibited is?
spatial summation
junction between 2 cells at which the electrical activity in one cell influences the electrical or metabolic activity of a second cell.
synapse
most synpases in the body are chemical/electrical?
chemical esp in the brain
major neurotransmitter in PNS at NMJ and brain
Ach
example of biogenic amines?
catecholamines such as epi and nor epi, serotonin, histamine
most prevalent neurotransmitter in the CNS are?
excitatory: glutamate and aspartate
inhibitory: GABA; glycine - released by spinal cord
Somata of preganglionic neuron in sympa is found in?
Para?
sympa: T1 to L4
para: CN 10, 9, 7, 3 and S1 to S4
length of preganglionic fibers in contrast to postgang fibers in sympa is? para is?
sympa: the pregang is shorter
parasympa: the pregang is longer
fibers that release Ach are considered to be?
cholinergic
fibers that release norepinephrine are considered?
adrenergic
all pre ganglionic neurons are considered? cholinergic or adrenergic?
cholinergic
almost all post gang fibers of the parasympa are choli/adrenergic?
cholinergic
most of post gang sympathetic neurons are choli/adre?
adrenergic EXCEPT: sweat glands and peripheral blood vessels which are cholinergic.
what gland is singly innervated by the sympa nervous system?
sweat glands; however they are cholinergic in nature