Which of these statements about myelination in neurons is/are correct? Select True or False for each statement.
T/FIt speeds propagation by increasing the density of voltage-gated channels all along the axon.
T/FMultiple sclerosis is characterized by disrupted myelination of certain neurons in the central nervous system.
T/FIt speeds propagation by preventing cations from leaking out across the membrane as they spread down the axon.
T/FIt is more commonly observed in vertebrates than in invertebrates.

Which ion most readily leaks across a neuron's membrane, helping to establish the resting potential?

A common feature of action potentials is that they

a. Cause the membrane to hyperpolarize and then depolarize

b. Can undergo temporal and spatial summation

c. Are triggered by a depolarization that reaches threshold

d. Move at the same speed along all axons

Where are neurotransmitter receptors located?

a. The nuclear membrane

b. The nodes of Ranvier

c. The postsynaptic membrane

d. Synaptic vesicle membranes

In a neuron, what creates the electrochemical gradient favoring the outflow of K⁺ when the cell is at rest?

a. Na⁺/K⁺-ATPase

b. Voltage-gated K⁺ channels

c. Voltage-gated Na⁺ channels

d. Ligand-gated Na⁺/K⁺ channels

Why are action potentials usually conducted in one direction?

a. Ions can flow along the axon in only one direction

b. The brief refractory period prevents the reopening of voltage-gated Na⁺ channels

c. The axon hillock has a higher membrane potential than the terminals of the axon

d. Voltage-gated channels for both Na⁺ and K⁺ open in only one direction.