Neuroendocrine Control Part 2
1. How do neurons communicate and what are the two main types?: Through synapses
- Chemical and Electrical
2. Define chemical neural communication: Neurotransmitter used to communi- cate into a
synapse
3. Define electrical neural communication: Ions from directly through tight junc- tions
4. Is inhibitory depolarizing or hyperpolarizing?: hyperpolarizing
5. Is excitatory depolarizing or hyperpolarizing?: depolarizing
6. How do dendrites find neurotransmitter?: Dendrites move chemotaxically to- wards NTs as
they are not directly attached to the axons
7. What are the steps of a chemical synapse?: 1. Action potential reaches axon terminal and
depolarizes membrane
2. Voltage gated Ca+ channels open to allow Ca+ in
3. Ca+ influx triggers vesicles to fuse with membrane and NTs release
4. NTs target receptors and bind to dendrites
8. How do blood vessels maintain their tone? How does frequency change differ if constriction or
dilation is needed?: Through continuous stimulation of certain frequencies, like 1/second,
determined after NT are removed from the synapse
- Constriction increases firing frequency
- Dilation decreases firing frequency
9. What are three ways that a NT signal can be terminated?: Reuptake by presynaptic neuron
Degradation by enzyme Diffuses
away from synapse
10.What is synaptic flexibility? How do presynaptic and postsynaptic control differ?: - Allows
flexibility in neural communication
- Presynaptic: Adjusts intensity/frequency of NTs released (quantity of NTs)
- Postsynaptic: Variability in receptor count or affinity
11.What is upregulation and downregulation?: Postsynaptic chemical synapse control
- Upregulation: Increase of receptor count and affinity
- Downregulation: Decrease of receptor count and affinity
12.What is synaptic plasticity? What processes is this crucial for?: Changes in the signaling
based on internal state or external cues
- Important for memory, learning, and addiction
13.What is NT diversity?: Different NTs being produced by different cells and received by
different receptors
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, Neuroendocrine Control Part 2
14.Describe electrical synapse in terms of gaps, flow, and speed. What is an example of where
this is found?: - Direct physical connections through gap junctions allow for a direct,
bidirectional, and rapid pathway of ions for immediate response.
- Found in reflexes
15.How do electrical synapse allow for bidirectional flow? Are electrical synapses able to perform
synchronized activity?: - Ions diffuse following con- centration gradient, making the pre and
post synaptic distinction blurry
- Yes! Through brain coordinated activity across groups of neurons
16.What are limitations of electrical synapses?: - Lack of modulation: Lack to ability to fine-
tune responses or to convert excitatory/inhibitory signals
- Reduced flexibility: Less adaptable, limiting their role in complex processing like learning
17.Describe neuromodulation and in which synapses it occurs?: Shows how neuromodulator
neurons affect post synaptic chemicals by strengthening or lessen- ing responses via NTs
(dopamine, serotonin, etc.)
- Occurs in chemical synapses only
18.What are conventional neurotransmitters?: NTs stored in synaptic vesicles and released
when Ca2+ enters the axon terminal
19.Name the primary excitatory and inhibitory NTs of the brain and spinal cord. What do effects
rely on?: - Excitatory of brain and spinal cord: Glutamate
- Inhibitory of brain: GABA
- Inhibitory of spinal cord: Glycine
Inhibitory/Exc effects depends on type/nature of receptors
20.Give an example of an inhibitory and excitatory acetylcholine receptor.: - Excitatory: Nicotinic
receptors at the neuromuscular junction (OR Muscarinic in the GI tract)
- Inhibitory: Muscarinic in the heart
21.Differentiate Ionotropic/ligand-gated and Metabotropic receptors.: - Ionotropic/Ligand: Ach binds
and allows ions to flow in, allowing muscle contraction. Occurs rapidly
- Metabotropic: Binding to receptor triggers second messenger, indirectly open- ing/closing
channels. Occurs slowly.
22.What are unconventional NTs and give examples. What are the two types?-
: Neurotransmitters not stored in synaptic vesicles
- Endocannabinoids
- Gasotransmitters
23.Explain endocannabinoids and what they control.: - May act as a retrograde NTs as it diffuses
based on concentration.
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1. How do neurons communicate and what are the two main types?: Through synapses
- Chemical and Electrical
2. Define chemical neural communication: Neurotransmitter used to communi- cate into a
synapse
3. Define electrical neural communication: Ions from directly through tight junc- tions
4. Is inhibitory depolarizing or hyperpolarizing?: hyperpolarizing
5. Is excitatory depolarizing or hyperpolarizing?: depolarizing
6. How do dendrites find neurotransmitter?: Dendrites move chemotaxically to- wards NTs as
they are not directly attached to the axons
7. What are the steps of a chemical synapse?: 1. Action potential reaches axon terminal and
depolarizes membrane
2. Voltage gated Ca+ channels open to allow Ca+ in
3. Ca+ influx triggers vesicles to fuse with membrane and NTs release
4. NTs target receptors and bind to dendrites
8. How do blood vessels maintain their tone? How does frequency change differ if constriction or
dilation is needed?: Through continuous stimulation of certain frequencies, like 1/second,
determined after NT are removed from the synapse
- Constriction increases firing frequency
- Dilation decreases firing frequency
9. What are three ways that a NT signal can be terminated?: Reuptake by presynaptic neuron
Degradation by enzyme Diffuses
away from synapse
10.What is synaptic flexibility? How do presynaptic and postsynaptic control differ?: - Allows
flexibility in neural communication
- Presynaptic: Adjusts intensity/frequency of NTs released (quantity of NTs)
- Postsynaptic: Variability in receptor count or affinity
11.What is upregulation and downregulation?: Postsynaptic chemical synapse control
- Upregulation: Increase of receptor count and affinity
- Downregulation: Decrease of receptor count and affinity
12.What is synaptic plasticity? What processes is this crucial for?: Changes in the signaling
based on internal state or external cues
- Important for memory, learning, and addiction
13.What is NT diversity?: Different NTs being produced by different cells and received by
different receptors
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8
, Neuroendocrine Control Part 2
14.Describe electrical synapse in terms of gaps, flow, and speed. What is an example of where
this is found?: - Direct physical connections through gap junctions allow for a direct,
bidirectional, and rapid pathway of ions for immediate response.
- Found in reflexes
15.How do electrical synapse allow for bidirectional flow? Are electrical synapses able to perform
synchronized activity?: - Ions diffuse following con- centration gradient, making the pre and
post synaptic distinction blurry
- Yes! Through brain coordinated activity across groups of neurons
16.What are limitations of electrical synapses?: - Lack of modulation: Lack to ability to fine-
tune responses or to convert excitatory/inhibitory signals
- Reduced flexibility: Less adaptable, limiting their role in complex processing like learning
17.Describe neuromodulation and in which synapses it occurs?: Shows how neuromodulator
neurons affect post synaptic chemicals by strengthening or lessen- ing responses via NTs
(dopamine, serotonin, etc.)
- Occurs in chemical synapses only
18.What are conventional neurotransmitters?: NTs stored in synaptic vesicles and released
when Ca2+ enters the axon terminal
19.Name the primary excitatory and inhibitory NTs of the brain and spinal cord. What do effects
rely on?: - Excitatory of brain and spinal cord: Glutamate
- Inhibitory of brain: GABA
- Inhibitory of spinal cord: Glycine
Inhibitory/Exc effects depends on type/nature of receptors
20.Give an example of an inhibitory and excitatory acetylcholine receptor.: - Excitatory: Nicotinic
receptors at the neuromuscular junction (OR Muscarinic in the GI tract)
- Inhibitory: Muscarinic in the heart
21.Differentiate Ionotropic/ligand-gated and Metabotropic receptors.: - Ionotropic/Ligand: Ach binds
and allows ions to flow in, allowing muscle contraction. Occurs rapidly
- Metabotropic: Binding to receptor triggers second messenger, indirectly open- ing/closing
channels. Occurs slowly.
22.What are unconventional NTs and give examples. What are the two types?-
: Neurotransmitters not stored in synaptic vesicles
- Endocannabinoids
- Gasotransmitters
23.Explain endocannabinoids and what they control.: - May act as a retrograde NTs as it diffuses
based on concentration.
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