Bio 212 Exam 4 Iowa State EXAM Questions &
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Terms in this set (34)
What is the action of acetylcholine Action Site: Excitatory
and where is the site of action? Neuromuscular junction some CNS pathways
Acetylcholinesterase inhibitors, Increase synaptic Transmission
often used to treat neurobiological
disorders:
Researchers find a compound that Increase synaptic transmission
when applied to neurons, activates
a protein involved in vesicle fusion
with a presynaptic membrane. This
compound would:
Resting Potential Na- and K- channels are closed
K- is concentrated inside the cell
Depolarization Na- channels open in response to a stimulus
Na-rushes into the cell
Repolarization Na- channels close and K- channels open
K- rushes out of the cell
, Hyperpolarization Na- and K- channels are closed
Sodium/potassium pump moves Na- out and K-
in
Steps that Occur when an action 1. Action potential (depolarization) opens voltage
Potential reaches the axon terminal gated Ca++ channels
2. Ca++ enters the presynaptic terminal and
triggers exocytosis releasing neurotransmitter
into synaptic cleft
3. Transmitter diffuses across cleft and binds to
ligand gated channels or receptors in
postsynaptic cell membrane
4. Binding of neurotransmitter changes
membrane potential of postsynaptic cell. Can be
excitatory or inhibitory
5. To end synaptic signal-neurotransmitter in cleft
is broken down or re uptake into presynaptic
terminal for repackaging into vesicles.
Characteristics of Schwann Cells Part of the PNS
Make up the myelin sheath
Keep ions from leaking out of the axon
Benefits of a Myelin Sheath Layers of the myelin membrane insulate the axon
membrane
Myelinated axons conduct impulses faster than
unmyelinated axons
How does Pufferfish toxin It inhibits the opening of voltage gated Na+
(tetrodotoxin) affect an action channels
potential?
Answers | 100% Verified solutions | Latest!!
Save
Terms in this set (34)
What is the action of acetylcholine Action Site: Excitatory
and where is the site of action? Neuromuscular junction some CNS pathways
Acetylcholinesterase inhibitors, Increase synaptic Transmission
often used to treat neurobiological
disorders:
Researchers find a compound that Increase synaptic transmission
when applied to neurons, activates
a protein involved in vesicle fusion
with a presynaptic membrane. This
compound would:
Resting Potential Na- and K- channels are closed
K- is concentrated inside the cell
Depolarization Na- channels open in response to a stimulus
Na-rushes into the cell
Repolarization Na- channels close and K- channels open
K- rushes out of the cell
, Hyperpolarization Na- and K- channels are closed
Sodium/potassium pump moves Na- out and K-
in
Steps that Occur when an action 1. Action potential (depolarization) opens voltage
Potential reaches the axon terminal gated Ca++ channels
2. Ca++ enters the presynaptic terminal and
triggers exocytosis releasing neurotransmitter
into synaptic cleft
3. Transmitter diffuses across cleft and binds to
ligand gated channels or receptors in
postsynaptic cell membrane
4. Binding of neurotransmitter changes
membrane potential of postsynaptic cell. Can be
excitatory or inhibitory
5. To end synaptic signal-neurotransmitter in cleft
is broken down or re uptake into presynaptic
terminal for repackaging into vesicles.
Characteristics of Schwann Cells Part of the PNS
Make up the myelin sheath
Keep ions from leaking out of the axon
Benefits of a Myelin Sheath Layers of the myelin membrane insulate the axon
membrane
Myelinated axons conduct impulses faster than
unmyelinated axons
How does Pufferfish toxin It inhibits the opening of voltage gated Na+
(tetrodotoxin) affect an action channels
potential?
