Week 2

Question 1

The resting potential of a neuron

Answer 1

-70mV difference between inside and outside of cell

Question 2

Concentration of ions inside and outside a cell at resting state

Answer 2

High concentration of sodium ions outside cell, high concentration of potassium ions inside cell

Question 3

Steps involved in an action potential

Answer 3

1. Depolarising stimulus of +15mV (raising it to -55mV) at axon hillock
2. Sodium rushes into cell, potassium channels open, sodium channels close
3. Potassium rushes out of cell, potassium channels close
4. Refractory period

Question 4

How are ions charged

Answer 4

Electrons are negatively charged; so an absence of electrons = positively charged. A surplus of electrons = negatively charged

Question 5

Sodium

Answer 5

Na+

Question 6

Potassium

Answer 6

K+

Question 7

Calcium

Answer 7

Ca2+

Question 8

Chloride

Answer 8

Cl-

Question 9

Organic

Answer 9

A-

Question 10

Steps involved in an action potential

Answer 10

1. Depolarising stimulus of +15mV (raising it to -55mV) at axon hillock
2. Sodium rushes into cell, potassium channels open, sodium channels close
3. Potassium rushes out of cell, potassium channels close
4. Refractory period

Question 11

Organic

Answer 11

A-

Question 12

Sodium Potassium Pump

Answer 12

3 sodium ions out for every 2 potassium ions in (ie continuously exchanges three intracellular Na+ for two K+)

Question 13

Sodium Potassium Pump

Answer 13

3 sodium ions out for every 2 potassium ions in

Question 14

Diffusion Forces

Answer 14

Particles move away from areas of high concentration

Question 15

Electrostatic Forces

Answer 15

Like charges repel each other

Question 16

Threshold Potential

Answer 16

Typically voltage inside the neuron becomes more positive by about +15mV (making the charge (-55mV), triggering an action potential

Question 17

Voltage at peak of action potential

Answer 17

+30mV

Question 18

Exocytosis

Answer 18

The process by which neurotransmitters are released into the synapse

Question 19

What is white matter made of?

Answer 19

Myelinated axons

Question 20

What is grey matter made of?

Answer 20

Cell bodies

Question 21

What is grey matter made of?

Answer 21

Cell bodies

Question 22

All or none law

Answer 22

Once an action potential is triggered, it is always the same size. The threshold potential being reached is the catalyst for an action potential

Question 23

Direct agonist

Answer 23

Drug that binds with and activates a receptor

Question 24

Receptor blocker

Answer 24

A drug that binds with a receptor but does not activate it prevents the natural ligand from binding with the receptor (antagonist)

Question 25

Direct antagonist

Answer 25

Synonym for Receptor Blocker

Question 26

Noncompetitive binding

Answer 26

Binding of a drug to a site on a receptor; does not interfere with the binding site for the principal ligand

Question 27

Indirect antagonist

Answer 27

A drug that attaches to a binding site on a receptor and interferes with the action of receptor, but without interfering with the binding of the principal ligand

Question 28

Indirect agonist

Answer 28

A drug that attaches to a binding site on a receptor and facilitates the action of the receptor; does not interfere with binding site of principal ligand

Question 29

EPSP

Answer 29

Excitatory Post Synaptic Potential - Causes cell to become more positive

Question 30

IPSP

Answer 30

Inhibitory Post Synaptic Potential - Causes cell to become more negative

Question 31

Voltage during refractory period

Answer 31

Gets down to -80mV

Question 32

Presynaptic Inhibition

Answer 32

Receptors on the axonal endings that inhibit exocytosis, rather than inhibiting the postsynaptic neuron (GABA does this by stopping inflow of calcium at the axon terminal)

Question 33

Ionotropic Receptors

Answer 33

Same molecular unit for receptor and ion channel

Question 34

Metabotropic Receptors

Answer 34

Receptor activates a G Protein, instigating a number of intracellular chemical processes involving second messengers (opens many ion channels from 'inside' the neuron)

Question 35

Astrocytes

Answer 35

Star-shaped glial cells. Support neurons and provide structure. Form the blood-brain barrier.

Question 36

Astrocytes

Answer 36

Star-shaped glial cells. Support neurons and provide structure. Form part of the blood-brain barrier.

Question 37

Oligodendrocyte

Answer 37

Glial cells that wrap around CNS neurons to provide myelin sheath

Question 38

Swann Cells

Answer 38

Glial cells that wrap around PNS neurons to provide myelin sheath

Question 39

Swann Cells

Answer 39

Glial cells that wrap around PNS neurons to provide myelin sheath

Question 40

Function of a neuron

Answer 40

Encoding memories; production of thoughts and memories; the production of neurotransmitters

Question 41

Nerve impulse describes:

Answer 41

The movement of an action potential along the axon

Question 42

Dendrites receive what sort of input? Inhibitory or excitatory?

Answer 42

Both

Question 43

Saltatory conduction

Answer 43

At each node of ranvier, the action potential is amplified to original intensity

Question 44

What is common of the postsynaptic membrane

Answer 44

Thickened appearance and receptor protiens

Question 45

Spatial summation

Answer 45

multiple inputs from multiple neurons adding up to trigger action potential

Question 46

Temporal summation

Answer 46

lots of signals from one neuron in quick succession, triggering an action potential

Question 47

What is common of the postsynaptic membrane?

Answer 47

Thickened appearance and receptor protiens

Question 48

Temporal summation

Answer 48

lots of signals from one neuron in quick succession, triggering an action potential

Question 49

The influx of what ions at the Synaptic Terminal causes exocytation?

Answer 49

Ca++; Calcium

Question 50

Where are neurotransmitters produced?

Answer 50

In the soma and synaptic terminals

Question 51

Where are neurotransmitters produced?

Answer 51

In the soma and synaptic terminals

Question 52

Acetylcholine is the classical neurotransmitter for:

Answer 52

All skeletal motor synapses