synaptic signalling Flashcards
The cell membrane is impermeable to ____.
charged ions
Synaptic signalling is mediated by the
regulated movement of ions across the membrane
Cells utilize active transport to
maintain ion gradients
In a resting neuron there is higher___inside the cell than outside, while there is higher____and____outside the cell than inside
K+
Na+ and Cl-
Since K+ concentrations are higher in the cell then out it is____to leave the cell. This is done by____
favourable. This is done by K+ leak channels
At equilibrium K+ moving out of the cell is___as that moving in. This is a balance between chemical and eletrical properties thus called____.
the same
electrochemical gradient. Since this will result in a change of charge across the membrane the membrane now has potential
For a single ion we can calculate membrane potential by using__
Nernst equation
In the neuron K+ is not the only thing contributing to the potential so we can use____to calculate Na+ and Cl- also.
Goldman equation
If one ion has a much higher permeability than the other two we can us ___to calculate the membrane potential
Nernst equation
Goldman?
When the relative permeability of one of the ions is very high, the Goldman equation reduced to the nernst equation for that ion.
Myelination of axons
causes the wave of depolarization/repolarization to jump between nodes, increasing the speed and efficiency of the action potential. Loss of myelination is associated with neurodegenerative diseases such as multiple sclerosis
produced by Schwann cells and olgiodendrytes
Changes in the membrane potential during action potential are mediated by
initial opening and closing of the Na+ channel depolarizing the membrane with ve+ charge flooding in and K+ flooding out repolarizing the membrane
When the positive charge reaches the ___ it causes opening of ion gated Ca+ channels. Ca+ then floods into the cell, causing___
synaptic bouton
the secretory vesicles containing neurotransmitter to fuse with the plasma membrane and release their contents into the synapse
H20 urea and glycerol are ___
small uncharged polar molecules
Channel proteins form__
hydrophilic channels
-passive
The dendrites in a neuron____. And axons ___
receives signals
transmits signals which is terminated in synaptic boutons
