Neurotransmission and Neuron Structure

______ send signals away from neurons whereas ______ receive signals from other neurons. Dendrites; axons Axons; synapses Synapses; dendrites Axons; dendrites

• dendrites; axons

• synapses; axons

• synapses; dendrites

• axons; dendrites

The point at which the terminal button of an axon and another neuron communicate is called ______; communication here is made possible by the release of ______.

• axon hillock; hormones

• presynaptic membrane; neurotransmitters

• synapse; hormones

• synapse; neurotransmitters

The spaces between the covered parts of an axon are called:

• nodes of Ranvier

• vesicles

• synaptic clefts

• ventricles

When the charge across the membrane of a neuron is about ______, the charge is called the ______. This is because there are ______.

• -70mV; resting potential; more negative ions inside the cell

• -85mV; action potential; more positive ions inside the cell

• -55mV; action potential; more negative ions inside the cell

• -70mV; resting potential; more positive ions inside the cell

If the stimulation of a cell is strong, the strength of the action potential produced would be:

• Weaker than that produced by weak stimulation

• Twice that produced by weak stimulation

• No different to that produced by weak stimulation

• Stronger than that produced by weak stimulation

When depolarization occurs ______; this allows the release of ______ into the ______.

• Sodium channels open; neurotransmitters; synaptic gap

• Potassium channels open; neurotransmitters; synaptic gap

• Calcium channels open; neurotransmitters; synaptic gap

• Calcium channels open; dopamine; cell body

Local anesthetic drugs take effect by which of the following mechanisms?

• block of internal sodium axon channels

• block of internal potassium axon channels

• blocking acetylcholine channels within local muscles

• inhibiting the action of neurotransmitter degraders

The opening of axon membrane potassium channels is responsible for what portion of the action potential?

• depolarization

• repolarization

• hyperpolarization

• polarization

• contraction of postsynaptic muscle fibers

Which of the following statements concerning the propagation of action potentials is NOT correct?

• Saltatory conduction occurs in myelinated nerve fibers

• During conduction of an action potential, current flows from the active area of the membrane to the adjacent inactive area, thereby decreasing the potential in the inactive area to threshold

• Action potential propagation is faster in myelinated fibers than in unmyelinated ones

• Action potential propagation is faster in large-diameter fibers than in small-diameter ones.

• Action potential propagation is faster for stronger stimuli than weaker stimuli

What type of neuron would carry information to a gland in your body?

• association

• motor

• afferent

• sensory