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 becoming depolarized, what are the first channels to open?

• Sodium

• Potassium

• Calcium

• ACTH

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

• -55 mV

• -60 mV

• 40 mV

• -75 mV

Tags

NGSS.HS-PS3-5

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

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

Which of the following is/are true of repolarisation?

• Na+ channels close

• K+ diffuses into the neuron

• The membrane potential becomes more negative

• Na+ diffuses out of the neuron

In the figure above, what is occurring at step #4?

• Neuron receives enough stimulation, threshold is reached

• Na⁺ channels open allowing Na⁺ to diffuse inward, depolarizing the membrane

• K⁺ channels open and Na⁺ channels open, action potential begins

• K⁺ channels open allowing K⁺ to diffuse out, repolarizing the membrane

• Na⁺ are being pumped out and K⁺ are being pumped into the cell