Basic Neuroscience

Question 0

In ENS, what is the effect of intensifying the stimulus?

Answer 0

The size of twitch contractions get bigger

Question 1

In electrical nerve stimulation, what happens when the ulnar nerve is stimulated?

Answer 1

The ADM muscle contracts

Question 2

In ENS, what happens when the frequency of the stimulus increases?

Answer 2

The muscle contraction goes from twitching to tetonic

Question 3

In what 2 clinical settings do we use ENS?

Answer 3

To measure nerve conduction velocity (e.g. check for carpal tunnel syndrome)

To test for myasthenia gravis (abnormal nerve-muscle transmission as muscle receptor cells are damaged)

Question 4

What are the two classifications of the nervous system?

Answer 4

Structure and Function

Question 5

What are the 2 nervous system types when functionally classified?

Answer 5

Somatic and Autonomic

Question 6

Which functional nervous system interacts with the external environment?
(deals with sensation - eyes, ears, balance and skin and Motor - skeletal muscle/movement)

Answer 6

Somatic NS

Question 7

Which functional nervous system regulates the internal environment/homeostasis (heart, blood vessels, lungs, kidneys, digestive system, glands, liver)?

Answer 7

Sympathetic NS and Parasympathetic NS

Question 8

Which functional nervous system do the sympathetic and parasympathetic systems fall under?

Answer 8

The Autonomic NS

Question 9

What is the basic functional unit of the nervous system?

Answer 9

Neurone

Question 10

What are the supporting cells called that support the neurones in the nervous system?

Answer 10

Neurolgia - they outnumber neurones by 10:1 and they act as nutrition for cells

Question 11

What does the cell body with dendrites act as in the neurone?

Answer 11

The input

Question 12

What does the myelin sheath do in the neurone?

Answer 12

Speed up electrical impulses

Question 13

What does the axon do in the neurone?

Answer 13

Impulses travel along it

It can be a really long nerve fibre e.g. big toe to spinal cord

Question 14

Does the white matter or grey matter in the brain contain axons/tracts of nerve fibres?

Answer 14

The white matter (you can see the myelin which is why it is white)

Question 15

Does the white matter or grey matter in the brain contain the nerve cell bodies and the main sites of nerve cells (cortex, basal nuclei)?

Answer 15

Grey matter

Question 16

Does the nervous system have internal connective tissue for support?

Answer 16

No - it has supporting cells called neuroglia

Neuroglia outnumber neurones by 10:1

Question 17

By how much do neuroglia outnumber neurones in the nervous system?

Answer 17

10:1

Question 18

Can the neuroglia be different shapes and sizes?

Answer 18

Yes they are

Astro ones are star shaped
Micro ones are small

Question 19

List the 4 types of neurones

Answer 19

No axon
Bipolar
Unipolar
Multipolar

Question 20

Neurons with no axons are called amacrine cells. Where do they transmit their signals from?

Answer 20

Their dendrites

Question 21

Do neurons ever have more than one axon?

Answer 21

No

Question 22

How many processes do unipolar, bipolar and multipolar neurones have?

Answer 22

Uni = one
Bi = two
Multi = lots

Question 23

Inputs arrive at the neurone via the d…………….., action potentials then go along the a…………. and the s……………… t……………. release outputs (neurotransmitters) to another neurone or muscles/tissues

Answer 23

Input = dendrites
APs along AXON
Output = SYNAPTIC TERMINALS

Question 24

Nerve cells can communicate with what 3 things?

Answer 24

Nerve cells Muscle Glands

Question 25

Oligodendrocytes in the CNS and schwann cells in the peripheral NS do what?

Answer 25

Wrap around the axon and produce myelin | MS sufferers have problems with this

Question 26

Which NS do the schwann and oligodendrocytes cells work on?

Answer 26

``` CNS = OLIGO Peripheral = schwann ```

Question 27

Nerve cells communicate with each other by sending an a.............. p.............. (electrical signal) from the p............... c...... across the s............../j................... to the ....................... ........ . A.................. P.....................are known as changes in membrane potential

Answer 27

Action Potential Pre-synaptic Cell Synapse/Junction Post-synaptic cell

Question 28

A resting cell membrane is known as p....................

Answer 28

Polarised (resting cell membrane)

Question 29

Is a polarised (resting) cell membrane negative or positive compared to the outside?

Answer 29

It has a negative charge - the inside is -70mv to -80mv

Question 30

When a resting cell membrane becomes depolarised, what has happened to it?

Answer 30

It has been stimulated

Question 31

What are the chain of events once the cell has been depolarised?

Answer 31

Sodium channels open and sodium floods in | The electrical potential in the cell becomes positive

Question 32

How does a cell re-polarise?

Answer 32

Sodium channels close Potassium channels open and potassium moves out Electrical potential turns normal and negative again

Question 33

If a cell membrane receives a small electrical stimulus below the threshold, is there an action potential?

Answer 33

No - a fixed size of AP is needed - a certain level of stimulus

Question 34

What does the presynaptic neurone release?

Answer 34

Neurotransmitters

Question 35

In the presynaptic neurone, what contains/releases NTs?

Answer 35

Vesicles

Question 36

Once released from the vesicles in the presynaptic neurone, what do the NTs cross to get to the postsynaptic neurone?

Answer 36

They diffuse across the synapse/synaptic junction

Question 37

Once the AP has caused the NTs to cross the synapse after being released by the vesicles in the presynaptic neurone, where do they bind to and go?

Answer 37

They bind to receptors in the post-synaptic neuron

Question 38

What part of the post-synaptic neurone is often an ion channel, that allows NTs to depolarise the membrane to cause an Action Potential?

Answer 38

Chemical synapse receptor

Question 39

What are the body's executive controllers? | Systems begin with N and E

Answer 39

The nervous and endocrine systems

Question 40

There are 2 types of NS classification; functional and structural. What NS fall into each of these?

Answer 40

Functional: Somatic/Autonomic Structural: CNS/PNS

Question 41

What is the basic unit in the NS?

Answer 41

Neurone

Question 42

What transmits action potentials/impulses?

Answer 42

Neurones

Question 43

Where do neurones release NTs?

Answer 43

Synapses