Synaptic Transmission Flashcards
Synapses are ___ zones of contact which one neuron communicates with ___
Specialized
Other neuron effector cells in muscle
The average neuron forms ___ connection and receives ___ inputs
1000 synaptic
10,000
2 types of synapses:
Electrical
Chemical
Electrical synapses have __ junction which are typically ___ and ___ nM
Gap
3.5nM
20nM
Electrical synapse ions are paired ____ which bridge the continuous ___ of 2 neurons
Hemichannels
Cytoplasm
The flow of electrical synapses is __directional through a larger (___) pore
Bi
1.5nM
Each hemichannel is is called a ___ and made of 6 ___
Connexon
Connexins
Connexins open by turning:
Clockwise
The postsynaptic response follows presynaptic stimulation how fast?
Fraction of a millisecond
Benefits of electrical synapses: 1) Extremely ____ transmission 2)Connect large numbers of ___ 3)___ resistance 4) may transmit ___ signals
1- rapid signal
2- neurons
3- Low
4- metabolic
Connection of a large number of cells allows ___ cells to act and ____ as ____ cell
Small
Coordinate
One large
Low resistance of electrical synapses allows lower ____ produced and makes it (easy/difficult) to reach threshold and fire action potentials?
Depolarization
Difficult
Metabolic signals include moderate sized organic compounds such as___,___,___
Moderate sized Messenger
IP3
cAMP
Small peptides
Which X-chromosome linked disease causes demyelinization and is a single mutation of connexin 32 (CX32) in Schwann cells?
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease affects ___ because it is an ___-linked gene mutation which affects which connexin in the Schwann cell
Males
X-linked
CX 32
CX32 is a ___ channels in the Schwann cell
Gap-junction
The synaptic cleft of a chemical synapses is ___nM and is most common between ___
20-40 nM
Neurons
Chemical synaptic delay is at least ___ms, usually ___ms or longer
0.5 ms
1-5 ms
Chemical synapses fire (uni/bi)-directionally?
Unidirectional
Chemical synapse: ___ opens the presynaptic nerve terminals, which releases ___. This opens the receptor on the post synaptic cell allowing ___ to fire an action potential
Ca+
Neurotransmitter
Na+
T/F Chemical synapses rely on the receptor to determine the reaction.
FALSE It’s not about the receptor, it is about the (neuro)transmitter
Inhibitory neurotransmitters ___polarize the postsynaptic membrane
Hyperpolarize
Excitatory neurtransmitters ___polarize the postsynaptic membrane
Depolarize
Chemical synapses:
AP in presynaptic cell causes ___ of ___ terminal
Depolarization
Presynaptic
Voltage gated Ca+ channels open allowing ___ to enter ___ terminal. This causes the release of ___ into synaptic cleft
Ca+
Presynaptic
Neurotransmitter
Neurotransmitter diffuses across ___ and combines with receptors on ____ membrane
Synaptic cleft
Post synaptic membrane
___ transmitters hyperpolarize postsynaptic membrane
Inhibitory