Brain chemicals

Question 1

Dopamine and parkinsons disease

Answer 1

-symptoms are muscle shakes, stiffness of muscles and slowness of movement, poor balance, depression, difficulties with speech and breathing

• associated with the death of a group of dopamine secreting neurones in the brain, leads to the reduction of dopamine

-dopamine is seen to be associated with the control and movement of movement and emotional responses, active in the frontal cortex

Question 2

Treatment of parkinsons disease

Answer 2

• aim to increase the concentration of dopamine in the brain
• cannot move into the brain from the bloodstream but the molecule used to make dopamine can
• molecule is called L-dopa and can be turned into dopamine

Question 3

Serotonin and depression

Answer 3

-serotonin is a neurotransmitter linked to feelings of reward and pleasure
- lack of this is linked to clinical depression (prolonged feelings of sadness, anxiety, loss of interest, restlessness)
-Ecstasy works by preventing the reuptake of serotonin and the effect is the maintenance of a high conc of serotonin

Question 4

How synapses are affected by drugs

Answer 4

-interfere with the normal functioning of a synapse

-affect the synthesis or storage of the neurotransmitter
-may affect the release of the neurotransmitter from the presynaptic membrane
-may affect the interaction between the neurotransmitter and receptors on postsynaptic membrane
-may prevent reuptake of the neurotransmitter back into the presynaptic membrane
-may prevent neurotransmitter from binding
- may inhibit enzymes involved in breaking down the neurotransmitter in the synaptic cleft

Question 5

Agonist effect

Answer 5

• the drug binds to a receptor and activates the receptor to produce a response
• meaning they basically have the same shape and bind as they think its the same

Question 6

antagonist effect

Answer 6

• the drug blocks the action of receptor preventing it from responding