(1) Nervous System

Question 1

These are specialized transmembrane proteins that allow the movement of specific ions across the cell membrane

Answer 1

Ion Channels

Question 2

In the nervous system, ion channels are essential for generating and transmitting electrical signals, enabling _____ between neurons and other cells.

Answer 2

communication

Question 3

What are the key features of ion channels?

Answer 3

selective permeability, rapid opening and closing, neuronal excitability

Question 4

a key feature of an ion channel is that it can be (3)

Answer 4

voltage-gated, ligand gated, mechanically gated

Question 5

What type of ion channel opens or close in response to changes in membrane potential?

Answer 5

Voltage-Gated Ion Channels

Question 6

Voltage-Gated Ion Channels are crucial for action potential ____ and ____

Answer 6

generation, propagation

Question 7

What are the three ions under voltage-gated ion channel?

Answer 7

sodium, potassium, calcium

Question 8

At what mV does Voltage-Gated Sodium Channels open?

Answer 8

~ -55mV

Question 9

When Voltage-Gated Sodium Channels allow Na+ influx, what happens?

Answer 9

depolarization (action potential)

Question 10

Why is Nav inactivated rapidly?

Answer 10

to prevent continuous firing

Question 11

Where is Nav found abundantly?

Answer 11

axon hillock, nodes of Ranvier

Question 12

When does the Kv channels open?

Answer 12

after depolarization

Question 13

Through what process do Kv restore the resting membrane potential?

Answer 13

repolarization

Question 14

Kv channels are important for maintaining this period for neurons

Answer 14

refractory period

Question 15

Where are Cav found?

Answer 15

synaptic terminals

Question 16

What do Cav channels trigger?

Answer 16

neurotransmitter

Question 17

Where else do Cav plays a role?

Answer 17

gene expression and synaptic plasticity

Question 18

What type of ion channels open in response to the binding of neurotransmitters or other molecules?

Answer 18

Ligand-Gated Ion Channels

Question 19

What do Ligand-Gated Ion Channels mediate?

Answer 19

fast synaptic transmission

Question 20

What does nAChRs stand for?

Answer 20

Nicotinic Acetylcholine Receptors

Question 21

Where can nAChRs be found?

Answer 21

neuromuscular junctions, CNS

Question 22

nAChRs are activated by Acetylcholine which allows what two ions’ movement?

Answer 22

potassium and sodium

Question 23

What does nAChRs lead to?

Answer 23

excitatory postsynaptic potentials (EPSPs)

Question 24

What is the main inhibitory neurotransmitter?

Answer 24

y-aminobutyric acid (GABA)

Question 25

What type of receptor under ligand-gated ion channels is activated by GABA?

Answer 25

GABA-A Receptors

Question 26

What does GABA-A Receptors allow?

Answer 26

Cl- influx

Question 27

What does the Cl- influx lead to?

Answer 27

hyperpolarization and inhibition

Question 28

The GABA-A Receptors are targeted by (3)

Answer 28

sedatives, anesthetics, and alcohol

Question 29

What are the two glutamate receptors?

Answer 29

NMDA and AMPA Receptors

Question 30

What does NMDA allow?

Answer 30

sodium and calcium entry

Question 31

What are Na+ and Ca+ important for?

Answer 31

synaptic plasticity and memory

Question 32

What do AMPA receptors allow?

Answer 32

sodium influx

Question 33

What does Na+ influx lead to in AMPA receptors?

Answer 33

rapid excitatory responses

Question 34

What is the dysfunction of the two glutamate receptors lead to?

Answer 34

neurodegenerative diseases and epilepsy

Question 35

What do mechanically-gated ion channels open in response to?

Answer 35

mechanical stimuli

Question 36

What are some examples of mechanical stimuli?

Answer 36

pressure, stretch, or sound waves

Question 37

Where can mechanically-gated ion channels be found?

Answer 37

sensory neurons

Question 38

What do the sensory neurons in mechanically-gated ion channels involve?

Answer 38

touch, hearing, and proprioception

Question 39

Two examples of mechanically-gated ion channels

Answer 39

Piezo channels (touch sensation) and TRP channels (temperature sensation)

Question 40

What are the 5 roles of Ion Channels in Action Potentials?

Answer 40

Resting Membrane Potential Depolarization Repolarization Hyperpolarization Return to Resting Potential

Question 41

How many mV does the Resting Membrane Potential have?

Answer 41

-70 mV

Question 42

The Resting Membrane Potential is maintained by what?

Answer 42

leak K+ channels and Na+/K+ pump

Question 43

How many mV does depolarization have?

Answer 43

~ -55 mV to +30 mV

Question 44

During what role is the voltage-gated Na+ channels open which allow Na+ influx?

Answer 44

Depolarization

Question 45

How many mV does repolarization have?

Answer 45

~ +30mV to -70mV

Question 46

During repolarization, the voltage-gated Na+ channels are what?

Answer 46

inactivate

Question 47

During what role of the ion channel leads to K+ efflux due to the opening of voltage-gated K+ channels?

Answer 47

Repolarization

Question 48

What is the role of ion channels when K+ channels stay open longer, overshooting the resting potential?

Answer 48

Hyperpolarization

Question 49

What kind of pump restores ion balance when returning to the resting potential?

Answer 49

Na+/K+ pump

Question 50

What disorder happens when there is a dysfunction in Na+ or K+ channels leading to excessive neuronal firing?

Answer 50

Epilepsy

Question 51

What is the disorder due to an autoimmune attack on nicotinic ACh receptors which causes muscle weakness?

Answer 51

Myasthenia Gravis

Question 52

When there is a mutation in voltage-gated Na+ channels, leading to inability to feel pain, what disorder happens?

Answer 52

Congenital Pain Insensitivity

Question 53

What is the disorder that happens when there is a dysfunction in the CFTR (Cl- channel) which leads to thick mucus in the lungs?

Answer 53

Cystic Fibrosis

Question 54

What blocks voltage-gated Na+ channels, preventing pain transmission?

Answer 54

Local Anesthetics

Question 55

What enhances GABA-A Receptor function, inducing sedation?

Answer 55

Benzodiazepines

Question 56

What reduces neuronal excitability by modulating sodium or calcium channels?

Answer 56

Antiepileptic Drugs

Question 57

What is an electrical signal that travels along our nerve cells that helps nerves communicate?

Answer 57

Action Potential

Question 58

Lidocaine is an example of what type of pharmacological targeting of ion channels?

Answer 58

Local Anesthetics

Question 59

Diazepam is an example of what?

Answer 59

Benzodiazepines

Question 60

Phenytoin is an example of what?

Answer 60

Antiepileptic Drugs