BIOL2401
Bonus Assignment: Neuron Action Potential (5 pts)
use another color for your answers*
The process of an action potential propagation along a neuron’s axon was discussed in lecture this week. The diagram below illustrates each step of the process from A to F.
A B C
D E F
⦁ Describe the image:
What is happening at each step of the image. Be sure to note what is happening at each neuron membrane potential, which ion channels are open/closed, and the direction of ion movement.
⦁ (-70 mV)
⦁ (-60 mV)
⦁ (+10 mV)
⦁ (+30 mV)
⦁ (-90 mV)
⦁ (-70 mV)
Label the neuron action potential graph below with corresponding A-F.
⦁ Explain the plausible meanings and/or purposes: From image A above, knowing the criteria of a resting membrane potential, what are the purple (+) charged balls? What are the orange (+) charged balls? What is the significance of their movement in/out of the neuron membrane? In addition, what do the purple doors and orange doors represent? Are they chemically-gated or voltage gated? How can you tell?
⦁ Discuss the potential consequences and/or implications of the image’s meaning: From what you have discussed in the descriptions above, why is the presence of a Na+/K+ pump critical for a neuron? What happens when a person dies, cellular respiration stops, ATP production stops, and thus, the Na+/K+ pump stops working? Explain your answer.
