Nervous System Basics

Question 1

Excitatory postsynaptic potentials are generally caused by ___ channels opening, while inhibitory postsynaptic potentials may be caused by ___ channels opening.

a. Ca2+; K+
b. Na+; Cl-
c. K+; Cl-
d. Cl-; K+

Answer 1

b. Na+; Cl-

Question 2

Which of the following is not one of the criteria a substance must meet to be considered a neurotransmitter?

a. A synthetic mechanism is present in the cell
b. Vesicles containing the substance move down the axon with the action potentials when the neuron is stimulated
c. Receptors for the proposed substance are present on the postsynaptic cell
d. There is a means for inactivating the substance

Answer 2

b. Vesicles containing the substance move down the axon with the action potentials when the neuron is stimulated

Question 3

The direct effect of depolarization of the presynaptic nerve terminal by the action potential is the

a. docking of vesicles at the active zones
b. activation of autoreceptors
c. opening of V-gated Ca2+ channels
d. packaging of neurotransmitter into vesicles

Answer 3

c. Opening of the V-gated Ca2+ channels

Question 4

Which statement regarding metabotropic receptors is false?

a. They are coupled to intracellular G proteins
b. The receptor has one subunit with seven transmembrane domains
c. When activated they can stimulate effector enzymes
d. The receptor itself is an ion channel that opens upon ligand binding

Answer 4

d. The receptor itself is an ion channel that opens upon ligand binding

Question 5

Ionotropic receptors may let in ___, which can then act as a(n) ___.

a. Na+; second messenger
b. Ca2+; kinase
c. Ca2+; second messenger
d. Cl-; effector enzyme

Answer 5

c. Ca2+; second messenger

Question 6

Environmental stimuli, sensory stimuli, and psychoactive drugs can trigger long-lasting changes in neuronal connectivity. Collectively, these changes are termed

a. dendritic spine plasticity
b. sensitization
c. synaptic plasticity
d. synaptic density

Answer 6

c. synaptic plasticity

Question 7

Which statement about neuropeptides is false?

a. Transport of the vesicles down the axon depends on action potential propagation
b. Necessary enzymes are packed into the vesicle with the protein precursor
c. Neuropeptides must be synthesized in the cell body
d. Neuropeptide replenishment after neural activity occurs more slowly than replenishment of classical neurotransmitters

Answer 7

a. Transport of the vesicles down the axon depends on action potential propagation

Question 8

Selective blockade of terminal autoreceptors for any neurotransmitter would lead to a(n)

a. Decrease in neurotransmitter release
b. Increase in cell firing
c. Decrease in cell firing
d. Increase in neurotransmitter release

Answer 8

d. Increase in neurotransmitter release

Question 9

Activating a metabotropic receptor cannot result in

a. changes in the levels of a second messenger
b. changes in gene expression
c. opening of a G protein-gated ion channel
d. opening of an ion channel within the receptor

Answer 9

d. opening of an ion channel within the receptor