Nervous System Flashcards
Multipolar neuron
multiple axon terminal = motor neuron/ interneuron
Bipolar neuron
less dendrite/ rare
Pseudo-unipolar neuron
: 2 axon terminals one each side/ frequent in sensory
3 types of nrurons
multipolar
bipolar
pseudo-unipolar
Glia cells
oligopendroylte
shcwan cell
astrocytes
microsatelite cell
microglia
ependymal
oligopendrolyte
makes mylin for several axon bodies
Schwan cells
makes mylin for one axon at a time
Astrocytes
provide nutrients and structural support
microsatelite cell
in PNS// provide nutrients and support to maintain synapse connection
microglia
in cns// phagocytosis eat away bacteria to protect brain
ependymal
cns in ventricles/ chorid picxus to make CSF
NEURAL COMMUNICATION
is electrical
resting potential
depolarisation
repolarisation
hyperpolarisation
explain resting membrane potential
this is at -70Mv
then when neurotansmitters bind to ligated channels
they allow annions in e.g Na+
this leads to neuron becoming more postie on inside
until it reaches action potential at -55Mv
explain action potential
at -55Mv the sodium gated channels open and Na+ goes into the cell and becomes more positive until it reaches +30Mv then sodium gated channels close (depolarisation)
the at +30Mv the potasium gated channels open and then pottasium leaves the cell and it becomes less positvie. until it returns down to -80Mv then the gates close (repolarisation)
then pumps using ATP pump K + in against gradient and Na+ out against gradient so it returns to -70Mv (hyperpolarisation)
absolute refractory
second action potential cannot be iniated at same time
relative refractory
neuron responds to a strong stimuli at same time it is stimulated
node of rannier
no mylin
high percentage of voltage gated channel
synapse
gap junction
chemical transfer
neurotransmmiters
diffusion across synapse
ligan gated channels
how does neurotransmitters communicate
pre synaptic neuron has action potential reach the axon terminals
here calcium voltage gated channels open and Ca2+ enters this cause vesicles of neurotransmitters to be released by exocytosis and diffuse across synapse and then bind with ligan gated creceptors on post synaptic neurons dendrites
either inhibit or excite
excite
glutamine
inhibit
gaba
layers of the brain membrane
meniniges
dura matter
archanoid matter
pia matter
dura matter
outermost layer
thick tough inelastic
archanoid matter
middle layer with archanoid trubeculae which contains csf
pia matter
inner most layer it is thin delicate covers external with blood vessels
dicephalon
thalmus - relays and is proccessing center
hypothalmus- autonomic control H.R/ BP/ respiration
control intergration.-/ limbic system and hormone regilation
mid brain
important region for motor control// sleep wake cycles and temp regulation
pons
relays information to cerebellum/ thalmus
contains subconsious motor
medulla obalangata
relays info and is autonomic center for regulation
corpus collosum
allows both hemispheres to relay info to each other
cerebral spinal fluid
cushions delicate neural structure
supports brain
transport chemical messengers/ waste product
blood supply
basiler artery- 2 arteries join medial and then divide into left and right posterior cerebral artery
internal cataroid artery 2 anrterior cerebral arteries
hemorraghe
leak on the brain
ischaemic
blood clott
4 lobes of brain
frontal
pariteal
temporal
occipical
frontal lobe
broccas area- speech production
primary motor cortex
associate motor cortex- sends info to primary
high functioning- personality/ behaviour
temporal lobe
memory/ lamguage/ understanding/ auditory cortex
wernickles area- speech comprohension
occipical lobe
sight/ visual information
pariteal lobe
sensory information
spinal chord
31 segments= 31 pairs
dorsal horn- sensory
lateral horn- autonomic
ventricle horn- motor
autonomic nervous system
regulates bp/hr/ temp
parasympathetic -creturn to rest- ganglia close to target cell or inside
sympathetic - fight or flight- ganglia- close to spinal chord
ganglion
bundle or nerve cell bodies
neurotransmitter at ganglia
ACH and nicotine receptors
symp-
noradrenaline bind to adrenic receptor and activates target cell
in sweet ACH to musacrine receptor
para- ACH binds to musacrine receptor
reflexes
an autonomic response to stimuli proccessed in spinal chord
it is quick
4 types of spinal reflexes
withdrawal- activation of motor neuron in muscle
crossed extension- sends info to opposite muscle to relax and extend
stretch - muscle fibres activated when muscle stretch
tendon- activatd by tendon stretch
