Choose That Channel
Which ligand channel closes the slowest?
Which closes the fastest?
Slowest - Metabotropic
Fastest - Ionotropic
Bonus - Why does ____ channel stay open longer?
____ ion enters the axon terminal, causing the vesicles to begin emptying their contents into the synapse
Ca2+
Bonus +100 - what does the calcium bind to?
What are the two main types of synapses found in the human nervous system?
Chemical and electrical
What channel(s) can cause ions to flow?
Always voltage gated channels and ionotropic while sometimes metabotropic
When does sodium stop entering the cell?
At the peak of the action potential
Which type of synaptic transmission is more common?
Most synaptic transmission in the mature human nervous system is chemical
What channel(s) is/are located in the axon, axon hillock, and axon terminal?
Voltage gated
What is the relative concentration of ions inside and outside the neuron before the action potential?
More potassium inside. More sodium outside. More chloride outside
Cells connected by gap junctions are said to be _____
electrically coupled
What causes each channel to open?
voltage gated / metabotropic / ionotropic
change in membrane potential / ligand / ligand
If __ channel is opened, an EPSP occurs.
If __ channel is opened, an IPSP occurs.
Na+
K+
What separates the presynaptic and postsynaptic membranes at chemical synapses?
synaptic cleft
Which channel is responsible for the beginning of an action potential?
Voltage gated sodium channels
Which ion is responsible for the hyper polarization following an action potential?
The extra potassium located outside the cell
In how many directions may an electrical synapse travel? A chemical synapse?
Unlike the vast majority of chemical synapses, electrical synapses are bidirectional