Action! Potentials

What is the term used to describe the electrical impulse that neurons fire?

• Synaptic signal

• Axon pulse

• Neural impulse

• Action potential

What does the sodium-potassium pump do?

• Generates electrical impulses directly

• Pumps two potassium ions in and three sodium ions out

• Pumps three potassium ions out and two sodium ions in

• Equalizes sodium and potassium across the membrane

Tags

NGSS.HS-LS1-3

What is the resting membrane potential of a neuron typically?

• +40 millivolts

• 0 millivolts

• -70 millivolts

• -55 millivolts

What type of gated channel opens in response to physical stretching of the membrane?

• Ligand-gated channels

• Voltage-gated channels

• Resistance-gated channels

• Mechanically gated channels

What is the primary function of myelin sheath in neuronal communication?

• To slow down the action potential

• To block the action potential

• To generate the action potential

• To insulate the axon and speed up the action potential

What happens when a neuron's membrane potential reaches about -55 mV?

• It triggers an action potential

• It hyperpolarizes

• It stops all electrical activity

• It reaches resting potential

What is the primary role of ion channels in neurons?

• To destroy unwanted ions

• To generate electrical charges

• To facilitate the diffusion of ions across the membrane

• To prevent any ions from entering the neuron

What does a higher frequency of action potentials in a neuron signify?

• No change in stimulus

• A stronger stimulus

• A malfunctioning neuron

• A weaker stimulus

What is the significance of the -70 millivolts in neurons?

• It is the threshold for an action potential

• It is the peak depolarization voltage

• It is the resting membrane potential

• It is the hyperpolarization state

What type of conduction occurs when the current leaps from one Node of Ranvier to the next?

• Segmental conduction

• Linear conduction

• Saltatory conduction

• Continuous conduction