Electrochemical Action Of Neurons

Question 1

Conduction

Answer 1

Movement of an electrical signal within neurons: dendrites -> cell body -> axon

Question 2

Transmission

Answer 2

Movement of a signal from one neuron to another as a result of chemical signalling across the synapse

Question 3

Resting potential

Answer 3

Difference in electric charge between the inside and outside of neuron’s cell membrane

Question 4

Action potential

Answer 4

Electrical signal conducted along the length of a neuron’s axon to a synapse

Question 5

Why does an AP

Answer 5

When electrical charge reaches threshold level, sodium specific channels open and Na+ ions rush in
; this raises the charge of the inside

Question 6

Saltatory conduction

Answer 6

Electric current passing down the length of a myelinated axon

Question 7

Nodes of Ranvier

Answer 7

Charge jumps from node to node along the axon

Question 8

Transmission between neurons Terminal buttons

Answer 8

Knoblike structures at the end of an axon and are filled with vesicles containing neurotransmitters

Question 9

Neurotransmitters

Answer 9

Chemicals that transmit information across the synapse to a receiving neurons dendrites

Question 10

Receptors

Answer 10

Parts of the cell membrane that receive NTs and either initiate or prevent a new electric signal

Question 11

Reuptake

Answer 11

NTs are absorbed by the terminal buttons of the presynaptic neurons axon or neighbouring glial cells

Question 12

Diffusion

Answer 12

NTs drift out of the synapse and can no longer reach receptors

Question 13

Autoreceptors

Answer 13

NTs can bind receptor sites on presynaptic neurons; release signal to stop releasing NTs if there is excess

Question 14

Acetylcholine (ACh)

Answer 14

Voluntary motor control; regulation of attention, learning, sleeping, dreaming, memory, deterioration = Alzheimer’s

Question 15

Glutamate

Answer 15

Excitatory NT; enhances transmission of info between neurons; too much = seizures

Question 16

GABA

Answer 16

Inhibitory NT;stops firing of neurons; too little = seizures

Question 17

Norepinephrine

Answer 17

Mood and arousal; states of vigilance and awareness of dangers; low levels = mood disorders

Question 18

Serotonin

Answer 18

Mood and arousal; regulation of sleep and wakefulness , eating, aggressive behaviour,
; low levels = mood disorders

Question 19

Endorphins

Answer 19

Act within pain pathways and emotion centres; dulls experience of pain and elevates mood

Question 20

Agonist

Answer 20

Increase action of a NT, binds to a receptor and activates the NT

Question 21

Antagonist

Answer 21

Diminish function of a NT; prevents the NT from acting or lessens it’s effect

Question 22

L-Dopa

Answer 22

When modified produces dopamine; ingestion causes neurons to produce more dopamine; agonist for dopamine

Question 23

Amphetamines

Answer 23

Stimulates release and prevents reuptake of norepinephrine and dopamime; excess NTs flood the synapse which increases activation of the receptors; agonists

Question 24

Opioids

Answer 24

Agonist for endorphins; feeling of calm and euphoria; effective antagonist that decreases the release of NTs involved I’m perception of pain

Question 25

Naloxone

Answer 25

Opioid; antagonist as it binds to opioid receptors blocking agonist from affecting neurons

Question 26

Prozac

Answer 26

Blocks reuptake of serotonin- SSRIs keeps serotonin in synapse longer to activate more receptors to improve mood; agonist for serotonin

Question 27

Propranolol

Answer 27

Beta blockers; blocks receptor site for norepinephrine in the heart; antagonist for NE as it prevents NE from binding to receptos which slows down the heart; anti-anxiety, antidepressants