31) Identify the correct sequence of steps in the generation of an action potential.

1. Activation of sodium channels and rapid depolarization

2. Inactivation of sodium channels and activation of potassium channels

3. Depolarization to threshold

4. Closing of potassium channels

A) 1, 3, 4, 2

B) 3, 1, 2, 4

C) 4, 3, 2, 1

D) 1, 3, 2, 4

E) 3, 1, 4, 2

32) Adrenergic synapses release the neurotransmitter

A) acetylcholine.

B) norepinephrine.

C) dopamine.

D) serotonin.

E) GABA.

33) Adrenergic neurons release the neurotransmitter ________.

A) serotonin

B) acetylcholine

C) GABA

D) dopamine

E) norepinephrine

34) Which ion is needed to trigger the release of acetylcholine, via exocytosis, into the synaptic cleft?

A) sodium

B) potassium

C) calcium

D) chloride

E) zinc

35) Which of the following neurotransmitters usually depolarizes postsynaptic neurons?

A) serotonin

B) dopamine

C) GABA

D) acetylcholine

E) monoamine oxidase

36) Which of the following is the correct order of events that occur at a cholinergic synapse?

1. Extracellular calcium enters the axon terminal, triggering the exocytosis of acetylcholine.

2. Acetylcholine is removed by acetylcholinesterase.

3. Acetylcholine binds to receptors and depolarizes the postsynaptic membrane.

4. Axon terminal depolarizes.

A) 2, 3, 1, 4

B) 1, 4, 3, 2

C) 4, 1, 2, 3

D) 3, 4, 1, 2

E) 4, 1, 3, 2

37) The specialized membranes that protect the spinal cord are termed

A) cranial meninges.

B) cranial mater.

C) spinal meninges.

D) spinal mater.

E) epidural membranes.

38) Which of the following contains a delicate network of collagen and elastin fibers through which cerebrospinal fluid circulates?

A) epidural space

B) dural sinus

C) arachnoid villi

D) subarachnoid space

E) pia mater

39) The ________ is the layer of the meninges that is in direct contact with the surface of the brain.

A) pia mater

B) subarachnoid space

C) dura mater

D) epidural space

E) arachnoid

40) Head injuries that damage cerebral blood vessels are serious conditions because

A) they could cause severe pain.

B) these spaces compress and distort the relatively soft tissues of the brain.

C) epicardial tissue will be affected.

D) the venous sinus will not drain.

E) pathways will be blocked.