Synaptic Transmission

Question 1

function of axon terminals

Answer 1

have axon buttons which pass nerve impulses from cell body to part they control

Question 2

function of cell body

Answer 2

contains cell nucleus and mitochondria for energy

Question 3

function of dendries

Answer 3

receive messages from other neurons to trigger action potential

Question 4

function of axon

Answer 4

extension of cell body which passes electrical impulse towards axon terminals

Question 5

function of myelin sheath

Answer 5

fatty deposits that provide insulating layer and speed up transmission

Question 6

function of nodes of ranvier

Answer 6

break along myelin sheath on the cell body

Question 7

Process of synaptic transmission

Answer 7

• action potential created by movement of ions changing charge of neuron
• electrical signal travels down axon to terminal buttons
• this activated vesicles so that they release neurotransmitters
• can bind with receptors, if enough binds this creates a new action potential
• may be destroyed by enzymes
• may be reuptaked so be in vesicles until next impulse

Question 8

Function of acetylcholine

Answer 8

• stimulate muscle contractions
• emotions eg anger
• memory and attention

Question 9

Function of noradrenaline

Answer 9

• mood control
• sleeping
• dreaming
• learning

Question 10

Function of dopamine

Answer 10

• emotion and cognitive functioning
• posture
• addictions

Question 11

Function of serotonin

Answer 11

• mood control
• pain
• sleep
• regulates body temperature

Question 12

Evaluation of neurotransmitters as explanation of behaviour

Answer 12

• nature/nurture- doesn’t show nurtured side complex social interactions affect behaviour- disadvantage
• reductionism- doesn’t take into account social learning theory, not taking into account other biological reasons- disadvantage
• science- empirical evidence, objective study- advantage
• individual differences- can’t generalise- disadvantage

Question 13

Effect of drugs on transmission process

Answer 13

• increases amount of dopamine in reward pathway
• causes feeling of euphoria
• excessive neurotransmitter activity reducing natural level of dopamine
• when drug leaves system person is left with low dopamine levels causing dysphoria
• makes person reliant on drug to feel euphoria

Question 14

Evaluation of synaptic transmission as explanation of addictive behaviour

Answer 14

Scientific- quantitative method- objective- PET scans- advantage
Useful- explain why people are addicted and find treatment- advantage
Reductionist- simple explanation doesn’t account for environmental factors - disadvantage
Social control- socially sensitive- discriminate against groups - disadvantage