Ch. 4 Module 1 Flashcards
Axodendritic synapse
begins at the axon terminal and connects to the dendrite
Axosomatic synapse
begins at the axon terminal and ends at the soma membrane
Axo-axonic synapse
begins at the axon terminal and ends at the axon terminal of a target neuron (has a presynaptic effect)
Why is meth the drug of choice compared to cocaine?
Meth lasts much longer as 50% of the drug is removed from the body 12 hours compared to cocaine 50% is removed after 1 hour. In addition, smoking meth produces a long lasting high
What kind of PSP will the receptor produce if it binds to a sodium or calcium channel?
EPSP
What kind of PSP will be produced if receptors bind to potassium of chloride channels?
IPSP
What does the intensity of the PSP depend on?
depends on the amount of neurotransmitters that is released into the cleft
What is temporal summation?
input from the same synapse over time
What is spatial summation?
input from many different synapses at the same time
What are the 3 principles of inotropic receptors:
- they are rapidly activated
- they have a local effect
- they are rapidly terminated
What are the effects of protein kinases?
- produce or block PSP’s
- activate protein synthesis.
What are the response characteristic of Metabotropic receptors:
- delayed onset
- broad effect in membrane
- sustained effect
Explain the differences between Iontropic vs Metabotropic Receptors?
Iontropic:
- fast on/off
- all or non on/off
- triggers action potentials
Metabotropic
- slower on/off
- can amplify or dampen signals
- triggers multiple post synaptic events, including action potentials
What would happen if we prevent K+ from leaving as quickly as usual?
it would increase the amount of time to produce an action potential due to spike broadening
What is the receptor on the terminal that is able to bind with the terminas own transmitter when released
presynaptic autoreceptor
What do neuromodulators do?
do not activate synapses, but they do enhance or inhibit the overall function of true synapses in the area.
What are synapses called that are directly connected to the next cell?
electrotonic synapse
What would happen if you reduced the size of the gap in a synapse? How would this affect transmission?
- if there is a smaller gap, a more effective activation of synapse (potentiation of that synapse)
Explain step 1 of LTP
- obtain a baseline measure
- present a single stimulation to the input pathway
- record the synaptic response at the target
- many synapses become active
- this is called the population spike
explain step 2 of LTP
- present at high frequency intense stimulation to the input pathway
- known as tetanus
- LTP requires intense stimulation of the synapse
Explain step 3 of LTP
- present a single stimulation identical to step 1
- need to compare the population spike from step 2 to baseline
- if LTP occurred, the spike will be larger
Explain how electronic conduction occurs?
Occurs at the gap junctions that are typically found in escape circuits or in heart cells that must fire synchronously. They provide rapid responses, but lack the flexibility seen in chemical neurotransmission
depolarizing synapses are referred to as what?
Excitatory
hyper polarizing synapses are referred to as what?
Inhibitory
