Biology Forums - Study Force

1)If a neuron has receptors for a particular neurotransmitter, it will also ________.
A. Respond in a similar way to an agonist of that neurotransmitter
B. Respond in a similar way to an antagonist of that neurotransmitter
C. Release that same neurotransmitter at its axon terminals
D. Take up that neurotransmitter using active transport to remove it from the synaptic cleft

2)The conduction of an action potential along an axon _______.
A. Is faster for a strong stimulus than a weak one
B. Is faster in unmyelinated nerve fibers than in myelinated nerve fibers
C. Decreases in amplitude as it is propagated along the axon
D. All of the above are true
E. None of the above are true

3)Ouabain, a specific inhibitor of the Na+-K+-ATPase, is applied to a neuron. The next action potential that fires after ouabain application will appear ________.
A. Larger than normal
B. The same as normal
C. Smaller than normal
D. No action potential will fire after ouabain is applied

4)During the rising phase of the action potential, _____.
A. Voltage-gated potassium channels are open
B. There is a decrease in the sodium permeability
C. Sodium moves down both a concentration and electrical gradient
D. The cell's membrane potential moves toward the equilibrium potential for potassium
E. Sodium permeability is enhanced by a feedforward process

D


Would love to say E, but C sounds correct as well. Your thoughts? In unmyelinated axons, action potentials are generated at sites immediately adjacent to each other and conduction is relatively slow. Degree of myelination speeds up transmission.

Try (C)

For #2 I was thinking E (none of the above) as well. For #3 I had D but was unsure of that answer and for #1 I had A. Good thing I have somewhere to double check my answers. Thanks a lot Duddy!