Pathways & Receptors
What are your fight or flight catecholamines? What division of the autonomic NS do they belong to?
epinephrine and norepinephrine.
sympathetic NS.
If in flight or fight mode, would Dr. Gardner run away from a bear?
No. She's never seen a bear.
In ___ neurons, voltage-gated Na+ channels are at Nodes of Ranvier & we don't lose ions due to insulation.
myelinated
What division of the autonomic nervous system is the adrenal medulla part of? When is it activated? What does it release?
sympathetic
fight or flight
releases catecholamines = norepinephrine & epinephrine
Which amino acid is helpful for long-term potentiation?
glutamate
What is a graded potential?
temporarily changing the charge of the cell (from rest)
In the parasympathetic NS, what does the postganglionic neuron release onto the target cell after acetylcholine is released onto the ganglion?
ACh = acetylcholine
Why do we need an action potential?
In order to release neurotransmitter from the presynaptic cell into the synapse
Explain what happens when a cell becomes depolarized during an action potential
Sodium channels open. Sodium flows into the cell, making its charge more positive.
Which cholinergic receptor can have either an inhibitory or excitatory effect, depending on the target cell?
muscarinic receptor
When ACh binds to skeletal muscle, it has an ___ effect. But when ACh binds to the heart, it has an ___ effect.
stimulatory, inhibitory
How does the cell become repolarized during an action potential?
Na+ channels close, K+ channels open, K+ moves out of cell --> becomes more negatively charged once again
Describe the entire taste pathway starting from eating food and ending at the primary gustatory cortex.
Eat and taste food --> 3 nerves translate taste = Vagus CN X, Glossopharyngeal CN IX, Facial CN VII --> Medulla Oblongata --> Thalamus --> Parietal Lobe at primary gustatory cortex
Name the steps that occur to release neurotransmitter into the synapse by exocytosis.
1. Action potential arrives at the synapse
2. This causes voltage gated Ca2+ channels to open
3. Ca2+ binds to sensor protein that stimulates fusion and exocytosis of neurotransmitter
Describe all of the steps of an action potential.
1. Resting Membrane Potential: negative charge
2. Depolarization: gated Na+ channels open, Na+ diffuses into the axon --> cell becomes more positively charged
3. Repolarization: Na+ channels close, K+ channels open, K+ moves out of cell --> becomes more negatively charged once again
4. Hyperpolarization: K+ channels stay open longer than time needed to return to resting potential = cells becomes more negatively charged than at initial resting potential
5. K+ channels close and charge of plasma membrane returns to resting potential with help of Na+/K+ pump