physiology Flashcards
influx of what ion causes depolarisation
sodium
efflux of what ion causes repolarisation
potassium
when a cell is depolarised what ion channels open
calcium channels - influx then a claim induced exocytosis of neurotransmitter
what is the most common neurotransmitter
glutamate
does glutamate active cation or anion receptors
cation (positively charged)
does GABA/glycine active cation or anion channels
anion (negatively charged)
does GABA/glycine cause depolarisation or hyperpolarisation
hyperpolarisation - inhibitory response
does glutamate cause depolarisation or hyper polarisation
depolarisation - excitatory response
what neurotransmitters can active inotropic ligand gated ion channels (nicotinic AcH receptor channels)
Glutamate, GABA, Glycine, ACh and Serotonin
these mediate fast neurotransmission
what neurotransmitters can activate metabotrophic G -protein coupled receptors- slow neurotransmission
all except glycine
metabrotropic receptor are muscarinic G protein receptors
what type of neurons are lower motor neurons - in terms of morphology
multipolar
what type of neurons are dorsal root ganglion/sensory neurons in terms of morphology
pseudo unipolar
what type of afferent fibres are nociceptor fibres and what lamina of rexed are they found in
laminae I and II A-delta and C fibres
what afferent fibres are in the DCML eg A, B, C
A-alpha and A-beta
what are the laminae of rexed for A-alpha and A-beta fibres respectively
A-alpha - laminae VII and IX
A-beta- laminae III and VI
what mechanoreceptors are responsible for detecting touch ? which of these is found in hairy skin
meissners corpuscles and merkels discs merkels seen in hairy skin
what motor neurons contract in response to stretch reflex
gamma motor neurons
what are the different kinds of muscle fibres
slow oxidative - type I
fast - type IIa and IIb,IIx
what type of muscle fibres are found in red meat and why is it red ?
type I- slow oxidative red as high myoglobin content
describe slow oxidative - type 1 muscle fibres
fatigue resistant. ATP from oxidative phosphorylation. slow contraction and relaxation
what type of muscle fibres get ATP mainly from glycolysis
type IIx (IIb too but not seen in man )
what type of fibres are involved in weight lifting
IIx
what type of muscle fibres involved in running
IIa
