Basic Neuroscience

Question 1

In terms of polarity, are neurons non-polarised, simple polarised or highly polarised?

Answer 1

Highly polarised

Question 2

What are the two major cell types in the nervous system?

Answer 2

Neurons and glia

Question 3

What is the primary role of glia?

Answer 3

To support neurons

Question 4

What do oligodendrocytes and Schwann cells do?

Answer 4

Myelinate axons of neurons

Question 5

Where are oligodendrocytes found?

Answer 5

CNS

Question 6

Where do Schwann cells work?

Answer 6

PNS

Question 7

What is grey matter?

Answer 7

Nerve cell bodies. Outside of the brain e.g. cortex and basal nuclei and inner part of the spinal cord

Question 8

What is white matter?

Answer 8

Axons and myelin. Inner part of the brain and outer part of the spinal cord.

Question 9

What are axons specialised for?

Answer 9

Transmission of information

Question 10

What are dendrites specialised for?

Answer 10

Receipt of information

Question 11

Can neurons reproduce or not?

Answer 11

They do NOT reproduce

Question 12

What can nerve cells communicate with?

Answer 12

Other nerve cells, muscle and glands

Question 13

What 2 things does the movement of charged ions across cell membranes depend on?

Answer 13

Diffusion (concentration gradient – ions want to move from high to low) and electricity (charged ions want to move to areas of opposing charge).

Question 14

What is the cell voltage/membrane potential?

Answer 14

The difference in charge from the different ions outside and inside the cell.

Question 15

What are the 3 ways that ions can move across the cell membrane?

Answer 15

Pumps, protein carriers and ion channels.

Question 16

During the resting membrane potential, where is the most sodium, outside or inside the cell?

Answer 16

Outside the cell. Sodium is positive, at resting potential the inside of the cell is negatively charged.

Question 17

Is the resting cell membrane polarised or depolarised?

Answer 17

Polarised

Question 18

When stimulation causes an action potential, what happens to the resting cell membrane?

Answer 18

It becomes depolarised as sodium channels open causing sodium ions to move into the cell and the inside of the cell becomes more positive. Repolarisation happens when the sodium channels close and the potassium channels open. Potassium moves out of the cell and the membrane potential returns to being negative.

Question 19

In order for an action potential to occur the stimulus has to…

Answer 19

Reach the threshold. If the stimulus doesn’t reach the threshold then no action potential occurs.

Question 20

What is the role of myelin?

Answer 20

It insulates the axon so that the action potential and travel quickly without dissipating out of the cell.

Question 21

The condition multiple sclerosis affects the myelin. How?

Answer 21

Myelin is attacked by the body’s own immune system so there is decreased conduction in axons.

Question 22

During an action potential when it reaches the axon end of the neuron it has to change from electric signals to ——– to cross the synapse.

Answer 22

Chemical signals

Question 23

When the neurotransmitter is released into the synaptic cleft they bind to receptors on the second neuron. What does this cause?

Answer 23

Ion channels are opened and sodium moves into the second neuron to start a new action potential.

Question 24

Name 7 neurotransmitters

Answer 24

Acetylcholine, adrenaline, noradrenaline, serotonin, GABA, dopamine and glutamate.

Question 25

Based on the direction of conducted impulses what do sensory neurons do?

Answer 25

Originate from the sensory receptors to the processor

Question 26

Based on the direction of conducted impulses, what do motor neurons do?

Answer 26

Conduct signals that originated in the CNS

Question 27

Where are interneurons?

Answer 27

Between sensory and motor neurons