The blood–brain barrier (BBB) separates the circulating blood from the brain and extracellular fluid in the central nervous system (CNS) and:

1. Functions to control the exchange of substances between blood and the extracellular fluid in the CNS

2. Is comprised of the cells that line the largest blood vessels in the brain

3. Is comprised of the cells that line the ventricles of the brain

4. Prevents diffusion of lipid soluble molecules from the blood to the brain

In the peripheral nervous system, the cells that are capable of forming a regeneration tube through which a severed peripheral axon can regrow are the:

1. Schwann cells
2. astrocytes
3. oligodendrocytes
4. microglia

The relatively static membrane potential of quiescent cells is called the:

All the following statements regarding the action potential are true except:
1. Only a relatively small number of ${\mathrm{Na}}^{+}$ and ${\mathrm{K}}^{+}$ ions actually diffuse across the membrane.
2. This event includes both positive and negative feedback loops.
3. The ${\mathrm{Na}}^{+}$/${\mathrm{K}}^{+}$ pumps are directly involved in creating the action potential.
4. During an action potential, the ${\mathrm{Na}}^{+}$ and ${\mathrm{K}}^{+}$ total concentration are not significantly changed.

A local anesthetic is a medication that causes reversible absence of pain sensation. They:
1. block the closure of voltage regulated potassium ion channels
2. stimulate the opening of voltage regulated potassium ion channels
3. block the opening of the voltage regulated sodium ion channels
4. stimulate the opening of voltage regulated sodium ion channels

What will respectively happen to the synaptic vesicles undergoing exocytosis and the amount of neurotransmitter release as the action potential frequency in a presynaptic neuron increases?

1. increases; increases
2. increases; decreases
3. decreases; increases
4. decreases; decreases

When an excitatory neurotransmitter is released and binds to a receptor on the postsynaptic membrane, the neurotransmitter:

1. stimulates the flow of K+ ions out of the cell
2. produces an EPSP
3. produces an IPSP
4. stimulates the flow of Cl- ions into the cell

When a receptor loses its sensitivity, they are said to be:

1. Summated

2. Transduced

3. Ablated

4. Adaptation

What would be true for the nociceptors?

1. Nociceptors respond to extreme stimuli

2. All nociceptors are located in the skin

3. Nociceptors are involved in noise perception

4. Nociceptor pathways of conduction cannot be inhibited

During accommodation reflex for near vision in the eye there is:
1. increased sympathetic stimulation of iris smooth muscle
2. relaxation of ciliary muscles and lens becomes more spherical
3. increased parasympathetic stimulation leading to relaxation of the ciliary muscles
4. increased parasympathetic stimulation leading to contraction of ciliary muscles