Key Area 3.3

Question 1

What are neurons?

Answer 1

Nerve cells

Question 2

What are neurons made up of?

Answer 2

A cell body, and fibres called dendrites and axons.

Question 3

What are the three types of neuron?

Answer 3

Sensory, inter, motor

Question 4

What is myelination?

Answer 4

The covering of neuron fibres with a myelin sheath which insulates them, increasing the speed of nervous impulses. This process continues from birth to adolescence

Question 5

What do glial cells do?

Answer 5

Physically support neurons and produce the myelin sheaths

Question 6

How do glial cells remove debris?

Answer 6

Phagocytosis

Question 7

What are synapses?

Answer 7

Gaps between neurons

Question 8

What are found in pre synaptic neurons?

Answer 8

Synaptic vesicles containing neurotransmitters

Question 9

What to nervous transmissions between neurons rely on?

Answer 9

Neurotransmitters secreted into the synaptic cleft

Question 10

What to receptors in the post synaptic membrane respond to?

Answer 10

Neurotransmitters

Question 11

Why must neurotransmitters be removed from the synaptic cleft?

Answer 11

To maintain sensitivity.

Question 12

How are neurotransmitters reused?

Answer 12

By being broken down by enzymes or being tea sores into the pre synaptic membrane

Question 13

What do receptors determine?

Answer 13

Whether a signal is excitatory or inhibitory

Question 14

What can synapses filter out?

Answer 14

Weak stimuli resulting from insufficient secretion of neurotransmitters

Question 15

What are neural pathways?

Answer 15

Routes taken by impulses though the nervous system

Question 16

What happens in converging neural pathways?

Answer 16

impulses from several neurons are passed to a single neuron.

Question 17

What happens in diverging neural pathways?

Answer 17

Impulses from one neuron are passed to several others.

Question 18

What happens in reverberating neural pathways?

Answer 18

Impulses are recycled round loop like pathways.

Question 19

Why are new neural pathways created?

Answer 19

To bypass areas of brain damage, to suppress reflexes or in response to sensory impulses

Question 20

What does creation of new neural pathways do?

Answer 20

Gives plasticity of response of response

Question 21

What are endorphins?

Answer 21

Neurotransmitters that stimulate neurons involved in reducing intensity of pain, creation of euphoria, appetite modulation and release of sex hormones

Question 22

When does endorphin production increase?

Answer 22

In response to severe injury, prolonged and continues exercise, stress and certain foods

Question 23

What does dopamine do?

Answer 23

induced the feeling of pleasure and reinforced particular behaviour in the reward pathway.

Question 24

What do agonist drugs do?

Answer 24

act like neurotransmitters and can enhance transmission.

Question 25

What do antagonistic drugs do?

Answer 25

Bind to specific receptors, blocking the action of a neurotransmitter.

Question 26

What can certain drugs inhibit?

Answer 26

Enzymes that degrade neurotransmitters or inhibit their reabsorption

Question 27

What can recreational drugs do?

Answer 27

Mimic neurotransmitters, resulting in mood change, alteration of perception and changes in cognition and behaviour.

Question 28

What do recreational drugs affect?

Answer 28

Neurotransmission in the reward pathway.

Question 29

What is sensitisation?

Answer 29

An increase in the number and sensitivity of receptors as a result of exposure to antagonistic drugs- this can lead to drug addiction.

Question 30

What is desensitisation?

Answer 30

A decrease in the number and sensitivity of receptors as a result of exposure to agonistic drugs- this can lead to drug tolerance.