Action Potentials

What number(s) on the graph represents the Resting Potential?

• 1 and 2
• 1 and 5
• 2 and 3
• 3 and 4

When a neuron is depolarized, what are the first channels to open?

• Sodium
• Potassium
• Calcium
• ACTH

Tags

NGSS.HS-PS2-5

When a neuron is resting, the inside of the axon has a ____________ charge.

• -55 mV
• -70 mV
• 40 mV
• -75 mV

When a neuron is not engaged in the transmission of an impulse.

• Resting potential

• Action potential

• Neural potential

• Synaptic potential

What number on the graph represents the Depolarization phase?

• 1
• 2
• 3
• 4

Tags

NGSS.HS-PS3-5

What number on the graph represents the Hyperpolarization phase?

• 1
• 2
• 3
• 4

Why is -55 mV a significant number?

• This is the largest charge achieved during an action potential
• This is the threshold required to complete an action potential
• This is the resting charge of a neuron
• This is the charge when all the sodium is inside the cell

Why is hyperpolarization important?

• It makes sure the neuron is healthy
• It prevents a second, unwanted signal from being sent
• It makes sure the neurons are in the correct space
• It makes sure the charge is back at -70 mV

Tags

NGSS.HS-LS1-3

Which of the following restores the resting membrane potential in a neurone?

I. Na+ channels opening

II. K+ channels closing

III. The Na+/K+ ATP pump

• I and II only

• II and III only

• I and III only

• III only

Why is the speed of an impulse increased if a neurone is wrapped in myelin?

• potassium ions flow out of the neurone faster

• myelin insulates the neurone so the temperature increases

• the impulse can jump from node to node

• it allows neurones to touch each other