Test 37  (neurophysiology)
1. The following are true about acetylcholine:
a. it is synthesized from acetyl-coenzyme A and choline

b. its formation is catalysed by acetylcholinesterase

c. at the synaptic cleft, it is inactivated by hydrolysis

d. reuptake by the presynaptic neurones play an important in inactivating 

e. acetylcholine receptors are found in all autonomic ganglia

2. The following are true about acetylcholine receptors:
a. receptors at all autonomic ganglia are nicotinic

b. receptors at the skeletal neuromuscular junction are muscarinic

c. acetylcholine receptors in the autonomic ganglia can be selectively blocked 
    by atropine

d. acetylcholine receptors in the neuromuscular junction can be selectively 
    blocked by  tubocurarine

e. pilocarpine is a muscarinic agonist

3. The following are true about the muscarinic receptors:

a. they are found at the postganglionic parasympathetic synapses

b. they can be selectively blocked by atropine

c. M1 muscarinic receptors are found in the brain

d. M4 muscarinic receptors are found in the pancreas

e. M2 muscarinic receptors mediate a positive chronotropic effect


4. The following are true about the autonomic nervous system:
a. the preganglionic fibres are mainly myelinated, slow conducting B fibres

b. the postganglionic fibres are mainly unmyelinated C fibres

c. all preganglionic neurones are cholinergic neurons

d. all sympathetic postganglionic neurons are adrengic neurons

e. the postganglionic neurons of the sympathetic pathway is longer than that 
    of the parasympathetic pathway.

5. True statements about the following neurotransmitters include:

a. dopamine is formed from tyrosine

b. in the synapse, noradrenaline is inactivated by active reuptake into the 
    presynpatic terminals

c. noradrenaline is formed by hydroxylation of dopamine

d. noradrenaline is oxidized by monoamine oxidase found in the presynpatic 

e. serotonin is formed from the amino acid tryptophan

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