Neurophys

Which of the following statements about neurons are NOT true?

• The resting membrane potential is generally in the range of -40mv to -75mv

• Maintaining resting membrane potential requires the use of Na-K pump

• An action potential can occur when the neuron's sodium gates open

• Neurons repolarize by opening sodium channels on the membrane

The resting membrane potential of neurons is determined by

• the permeability of the cell membrane to various ions

• the chloride ion concentration across the membrane

• the number of hydrogen ions located within the neuron

• the number of calcium ions located within the neuron

Resting neuron, the area just inside of the cell membrane is more _____ than the area just outside of the cell membrane.

• negative

• positive

• depolarized

• neutral

Depolarization

• is associated with increase in membrane permeability to Na+

• is terminated with closure of voltage activated K+channels

• is caused by K+efflux

• is followed by muscle relaxation

The hyperpolarization phase of the action potential is due to:

• the opening of voltage-gated Cl− channels

• due to the closure of Cl− channels

• the prolonged opening of voltage-gated K+ channels

• the closure of Na+ channels

Receptor sites for neurotransmitters are located on the

• tips of axons

• postsynaptic membrane

• presynaptic membrane

• in the nodes of Ranvier