central nervous system

Question 1

central nervous system

Answer 1

responsible for processing and integration of information around a body

Question 2

neuroscience

Answer 2

scientific study of the nervous system

Question 3

how many neurons in a person

Answer 3

100 billion

Question 4

where are most of the neurones located

Answer 4

brain (80%)

Question 5

nucleus

Answer 5

contains genetic material of the cell

Question 6

axon

Answer 6

a tube like structure that carried the impulses away from the cell body down the neuron

Question 7

myelin sheath

Answer 7

a fatty layer formed from special cells which wrap themselves around the axon

they protect the axon and speed up the electrical transmission of the impulse

Question 8

node of ranvir

Answer 8

gaps in the myelin sheath which increases the speed of impulse forcing them to jump across gaps

Question 9

axon terminal / terminal button

Answer 9

involved in communication across a gap called the synapse bit physically connected to the next neurone in the chain

Question 10

3 types of neuron

Answer 10

sensory neurons
motor neurons
relay neurons

Question 11

sensory neuron

Answer 11

carry messages from sensory receptors along nerves in peripheral nervous system to the cns

Question 12

sensory neuron structure

Answer 12

long dendrites
short axons

Question 13

motor neurons

Answer 13

carry messages from the cns along the pns to effectors in the body

Question 14

effectors example

Answer 14

muscles
glands

Question 15

motor neuron structure

Answer 15

short dendrites
long axons

Question 16

relay neurons

Answer 16

connect sensory and motor neurons together and also connect other relay neurons

Question 17

relay neuron structure

Answer 17

short dendrites
short axons
only found in cns

Question 18

neuron function

Answer 18

transmit messages throughout the body through electrical signals

Question 19

at resting stage what is the charge of the inside of a cell

Answer 19

negative

Question 20

describe neuron transmission

Answer 20

• when a neuron is activated by a stimulus the inside of the cell becomes positively charged creating an action potential
• action potential travels down axon towards terminal buttons

Question 21

what is depolarization

Answer 21

when a neuron is sufficiently activated by a stimulus and the inside of a cell becomes positively charged inside

Question 22

what is an action potential

Answer 22

an electrical impulse

Question 23

when can the action potential be generated

Answer 23

when depolarization reaches a certain threshold

Question 24

what does all or none event mean

Answer 24

• action potential is always same intensity regardless of the size of the stimulus that originally generated it
• if the threshold isn’t reached there’s no action potential
• it either creates an electrical impulse or it doesn’t

Question 25

how are signals within neurons transmitted

Answer 25

- chemically across the synapse

Question 26

synapse

Answer 26

small gap between 2 neurones

Question 27

what is synaptic transmission

Answer 27

a chemical process using biochemical substances called neurotransmitters

Question 28

what happens when the action potential reaches the end of a neuron

Answer 28

it triggers the release of neurotransmitters from sacs called synaptic vesicles

Question 29

neurotransmitters

Answer 29

chemicals that diffuse across the synapse to the next neuron

Question 30

what happens when neurotransmitters diffuse across the synaptic cleft

Answer 30

they fit into matching receptor sites on the post synaptic neuron

Question 31

what happens after the neurotransmitter reaches the synaptic neuron

Answer 31

it converts back into an electrical signal which may fire another action potential if the depolarization threshold is reached

Question 32

what happens to neurotransmitters that remain in the synapse

Answer 32

they are reabsorbed into the presynaptic neuron through proteins called transporters

Question 33

reuptake

Answer 33

when neurotransmitters that remain in the synapse are reabsorbed into the presynaptic neuron through transporters so they can be used again

Question 34

serotonin

Answer 34

a chemical messenger that acts as a neurotransmitter and hormone in the body it is a mood booster which causes inhibition in the post synaptic neuron causing the neuron to be more negatively charged

Question 35

dopamine

Answer 35

a chemical messenger in the brain that sends messages to other nerve cells in the body it is part of the brains reward system and creates pleasure, makes a post synaptic neurons more likely to fire

Question 36

acetylcholine

Answer 36

hells with muscle movements thinking and memory

Question 37

examples of neurotransmitters

Answer 37

serotonin dopamine acetylcholine

Question 38

vesicles

Answer 38

tiny sacs which trigger the release of neurotransmitters

Question 39

receptors

Answer 39

membrane proteins which receive neurotransmitters from pre synaptic neurones

Question 40

pres synaptic neurone

Answer 40

a nerve cell that sends information to another neurone across a synapse

Question 41

post synaptic neurone

Answer 41

a neurone that receives signals / neurotransmitters from another neurone at a synapse