Biology

When a neuron is depolarized, the gated channels of the membrane open to allow __________ to enter the neuron. A neuron becomes hyperpolarized when the gated channels of the membrane open thus allowing __________ to exit the neuron

• K+, Na+

• Na+, K+

• protein, Na+

• Na+, protein

In order to maintain an ionic charge balance across a neuron's membrane after depolarization, what ion is moved to the outside of the membrane to maintain the ionic charge?

• sodium

• chloride

• protein

• potassium

During repolarization, the sodium channels are closed. How does this affect a neuron?

• The neuron cannot respond to new stimuli

• The neuron becomes more sensitive to new stimuli

• It does not affect the neuron

• All of the above

Which factor primarily determines the speed of a nerve imoulse

• Axon diameter

• Mumber of dendrites

• Shape of the neuron

• Presence of neurotransmitters

Action potential occurs when

• The neuron is at resting potential

• The membrane potential reaches the threshold level

• Potassium ions enter the neuron rapidly

• The sodium-potassium pump stops working