Psychobiology

Question 1

How do the node of ranvier allow for conduction?

Answer 1

the node of ranvier are gaps between the myelin sheath which are rich in ion channels which are required to form an action potential. Allows for saltatroy conduction as the impulse jumps between the gaps.

Question 2

What does acetylocholine cause?

Answer 2

Rapid depolarisation

Question 3

How does an excitatory receptor work?

Answer 3

Binding of a neurotransmitter, open Na+ channel or both Na+ and K+. Leads to depolarisation of post synaptic plasma membrane promoting generation of an action potential.

Question 4

How does an inhibitory receptor work?

Answer 4

Causes opening of K+ or Cl- channels resulting in membrane hyperpolarization which inhibits generation of an action potential in post synaptic cell.

Question 5

Does myelination increase or decrease in adolescence?

Answer 5

Decreases

Question 6

Describe an agonist

Answer 6

Keeps receptors open for more uptake. e.g. SSRI- prozac (selective serotonin reuptake inhibitor)

Question 7

Describe an antagonist

Answer 7

Stops uptake and blocks receptor e.g. pain killers on pain receptors

Question 8

Function and malfunction of acetylcholine

Answer 8

Function- regulates motor control and contributes to attention, learning, memory, sleeping and dreaming
Malfunction- Alzheimer’s disease- Ach producing neurons break down

Question 9

Function and malfunction of dopamine

Answer 9

Function- influences movement, motivation, emotional pleasure and arousal
Malfunction- increase linked to Schizophrenia
decrease linked to producing tremors and decreased mobility in Parkinson’s.

Question 10

Function and Malfunction of Glutamate

Answer 10

Function- excitatory neurotransmitter involved in learning and memory
Malfunction- oversupply can overstimulate brain producing seizures

Question 11

Function and Malfunction of GABA

Answer 11

Function- Primary inhibitory neurotransmitter

Malfunction- Undersupply is linked to seizures, tremors and insomnia

Question 12

Function and Malfunction of noradrenaline

Answer 12

Function- Helps control mood and arousal

Malfunction- Undersupply can depress mood

Question 13

Function and Malfunction of serotonin

Answer 13

Function- Regulates hunger, sleep, arousal and aggressive behaviour
Malfunction- Undersupply- depression, prozac raises serotonin levels