Question

Voltage gated K+ channels open ____________, and ligand gated K+ channels open __________

a) When an inhibitory neurotransmitter binds to the receptor in the postsynaptic membrane, when an excitatory neurotransmitter binds to the receptor in the postsynaptic membrane

b)During the repolarization stage of an action potential, during the hyperpolarization stage of an action potential

c)During the depolarization stage of an action potential, during the repolarization stage of a action potential

d)During the repolarization stage of an action potential, when an inhibitory neurotransmitter binds to the receptor in the postsynaptic membrane

e)When an inhibitory neurotransmitter binds to the receptor in the postsynaptic membrane, during the repolarization stage of an action potential

Which of the following experimental manipulations would increase neurotransmitter release at the presynaptic terminal?

a) A decrease in intracellular Na+ concentrations at the axon terminal

b)An increase in extracellular Na+ and K+ concentrations at the axon terminal

c) A decrease in intracellular Ca++ at the axon terminal.

d) An increase in extracellular Ca++ concentrations at the axon terminal

e) An increase in intracellular K+ concentrations at the axon terminal

Answer 1

Answer- c)During the depolarization stage of an action potential, during the repolarization stage of a action potential

Voltage-gated potassium channels (VGKCs) are transmembrane channels specific for potassium and sensitive to voltage changes in the cell's membrane potential. During action potentials, they play a crucial role in returning the depolarized cell to a resting state.

ligand-gated ion channels are one type of membrane receptors. They are transmembrane ion channels that open or close in response to the binding of a chemical signal like a ligand. This will actually cause an intracellular electrical signal.