Which of the following is false regarding Na+ ion channels in a neuron?Group of answer choicesTheir concentrations are highest at the nodes of Ranvier.Na+ can move from an area of high concentration inside a cell to an area of low concentration outside the cell through these channels.They permit the movement of Na+ ions in only one direction.The Na+ ion channels are integral membrane proteins.

Which of the following statements best describes the movement of ions across the plasma membrane?Multiple ChoiceMovement of K+ ions depends on the concentration of Na+ ions to either side of the membrane.The ion channels contributing to the membrane potential are unidirectional.The membrane potential is contributed to only by ions with a positive charge.Each ion species follows its own diffusion gradient, regardless of differences in the concentration of other ion species.

The cell membrane of a neuron has both gated and non-gated ion channels. Which type of non-gated channel is more abundant?Multiple ChoiceNon-gated sodium channelsNon-gated potassium channels

What causes ion selectivity in channels?Group of answer choicesThe electrical resistance of the neuron.The specific pore size and charged residues along the pore.The amount of myelin around the axon.The length of the axon hillock

Movement of Na+ ions into a nerve cell during the upstroke of an action potential is an example of of the following transport mechanismSelect one:a. Facilitated diffusionb. Co-transportc. Primary active transportd. Simple diffusion

n normal neurons, K+ flows down concentration gradient out of cell, and Na+ flows down concentration gradient into cell.Group of answer choicesTrueFalse