Graded potential/Synaptic communication Flashcards
A membrane potential which initiates as a small local event which in turn might trigger an action potential is called what?
Graded potential (local/generator/receptor potential)
What are the two general things Graded potentials are involved with?
1-Originating sensory information
2-Receiving neurotransmitter signals from a synapse
Which type of potential (Action potential or Graded potential) is propagated?
Action potential
Which type of potential (Action potential or Graded potential) is bigger in terms of amplitude?
Action potential (100 mV)
*GP is 3-20 mV
Which type of potential (Action potential or Graded potential) has a longer duration?
Graded potential (ms-sec)
*AP is 1-2 ms
Which type of potential (Action potential or Graded potential) is localized?
Graded potential
*AP is cell wide
Which type of potential (Action potential or Graded potential) has an all or nothing threshold?
Action potential
Which type of potential (Action potential or Graded potential) has a refractory period?
Action potential
Which type of potential (Action potential or Graded potential) is decremental (degraded over distance)?
Graded potential
Which type of potential (Action potential or Graded potential) is spread by passive electrochemical mechanism?
Graded potential
*AP is voltage gated ion channels
What are the two types of summation of graded potentials?
1-spatial summation
2-Temporal summation
Collective activity of multiple graded potentials generated by different presynaptic neurons is called what?
Spatial summation
Repeated activity of graded potentials from the same presynaptic neuron is called what?
Temporal summation
Where is the electrical signal converted into a chemical signal?
bouton portion of the neuron
*dendrite of post-synaptic neuron converts chemical back to electrical signal
The zone that stores the elements necessary for a synapse is called?
the active zone
The area that is the receiving center and has receptors is called what?
post synaptic density
what presynaptic protein element binds a receptor on the post-synaptic neuron to provide mechanical stability for the synapse?
Neurexin
Opening of calcium channels in the bouton cause vesicles to fuse/expulse their contents via what proteins?
SNARE proteins (kiss and run hypothesis or complete fusion)
Orthograde transport means what?
full vesicle going toward synaptic bouton
Retrograde transport means what?
empty vesicle being recycled back to the cell body
What two speeds of axonal transport are there?
- Fast transport (400 mm/day)
- Slow transport (1-10 mm/day, lots of stop and go)
What are the main two types of neurotransmitters?
- Excitatory post synaptic potentials (EPSPs)
- Inhibitory post synaptic potentials (IPSPs)
A neuron can pass information in which two main ways?
- excitation (message sent)
- lack of signal (why didn’t they call)
