Lecture 8 VGSC, Synapses Flashcards
(26 cards)
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Blocks VGSC - puffersih
Batrachotoxin
opens channel irregularly - frogs
µ-Conotoxin
blocks channel - snails
Patch clamp
neural membrane removed via recording electrode tip using suction
Channels present are stimulated and individual ion currents measured
AP must propagate signal along
entire length of axon
AP are
self propagating; travel in only one direction
Nerve impulse
AP propagation down axon
conduction speed
rate of propagation influenced by both axon diameter and myelination
Axon with larger diameter
faster conduction speed - lower resistance
Myelinated neurons
fast signals through salutary conductions
Continuous conductions
Unmyelinated axon every section of axolemma from trigger zone to axon terminal must propagate action potentials
Saltatory conduction
the insulating properties of the myelin sheath increases efficiency and speed of signal conduction
AP only depolarize
nodes of reviver; jumps from node to node
channel rhodosin
gene is inserted into larger DNA of specific populations
Fiber optic cable
used to stimulated and modulate target control
presynaptic neuron
neuron sending message from its axon terminal
Postsynaptic neuron
neuron receiving message from presynaptic neuron at body, axon or dendrites
electrical synapses
occurs between cells electrically couple via gap junctions
Axolemmas of each cell in synapses are nearly touching;
gap junction align channels forming pores that ions or other small substances can flow through
Chemical synapse
Neurotransmitter signal between pre/postsynapse
- more efficient and used
convert AP into chemical signals
synaptic vesicle
transmit signals from pre/postsynaptic neurons through exocytosis
synaptic cleft
Separates presynaptic and postsynaptic neurons in chemical sequence
synaptic delay
time gap between arrival of AP at axon terminal and effect on postsynaptic membrane
the most neurotransmitter released…
stronger response at postsynaptic neuron
