Exercise 3: Neurophysiology of Nerve Impulses
EXERCISE 3: Neurophysiology of Nerve Impulses
ACTIVITY 1: The Resting Membrane Potential Answers
1. The nervous system contains two general types of cells: neuroglia cells and
a. nerves.
b. cell bodies.
c. neurons.
d. nephrons.
2. The resting membrane potential of the neuron in this lab under the control conditions was _______ mV.
3. True or False: For most neurons, the concentration of Na+ and K+ ions inside and outside the cell are the primary factors that determine the resting membrane potential.
4. Explain why increasing the extracellular K+ causes the membrane potential to change to a less negative value. 5. Discuss the relative permeability of the membrane to Na+ and to K+ in a resting neuron.
6. Discuss how a change in Na+ or K+ conductance would affect the resting membrane potential.
ACTIVITY 2: Receptor Potential
7. The “receiving end” of a sensory neuron is called the sensory receptor. It has proteins that can generate a signal called the _________ potential when the sensory neuron is stimulated.
8. Which of the following is not a sensory modality?
a. taste
b. smell
c. touch
d. height
9. The maximum amplitude of response of the Pacinian corpuscle to pressure in this simulation was ____ mV.
10. Sensory neurons have a resting membrane potential based on the efflux of potassium ions (as demonstrated in Activity 1.) What passive channels are likely found in the membrane of the olfactory receptor, in the membrane of the Pacinian corpuscle, and in the membrane of the free nerve ending?
11. What is meant by the term graded potential?
12. Identify which of the stimulus modalities induced the largest amplitude receptor potential in the Pacinian corpuscle.
13. Identify which of the stimulus modalities induced the largest amplitude receptor potential in the olfactory receptors.
14. What type of sensory receptor would likely respond to a green light?
ACTIVITY 3: The Action Potential: Threshold
15. In this lab simulation, what
ACTIVITY 1: The Resting Membrane Potential Answers
1. The nervous system contains two general types of cells: neuroglia cells and
a. nerves.
b. cell bodies.
c. neurons.
d. nephrons.
2. The resting membrane potential of the neuron in this lab under the control conditions was _______ mV.
3. True or False: For most neurons, the concentration of Na+ and K+ ions inside and outside the cell are the primary factors that determine the resting membrane potential.
4. Explain why increasing the extracellular K+ causes the membrane potential to change to a less negative value. 5. Discuss the relative permeability of the membrane to Na+ and to K+ in a resting neuron.
6. Discuss how a change in Na+ or K+ conductance would affect the resting membrane potential.
ACTIVITY 2: Receptor Potential
7. The “receiving end” of a sensory neuron is called the sensory receptor. It has proteins that can generate a signal called the _________ potential when the sensory neuron is stimulated.
8. Which of the following is not a sensory modality?
a. taste
b. smell
c. touch
d. height
9. The maximum amplitude of response of the Pacinian corpuscle to pressure in this simulation was ____ mV.
10. Sensory neurons have a resting membrane potential based on the efflux of potassium ions (as demonstrated in Activity 1.) What passive channels are likely found in the membrane of the olfactory receptor, in the membrane of the Pacinian corpuscle, and in the membrane of the free nerve ending?
11. What is meant by the term graded potential?
12. Identify which of the stimulus modalities induced the largest amplitude receptor potential in the Pacinian corpuscle.
13. Identify which of the stimulus modalities induced the largest amplitude receptor potential in the olfactory receptors.
14. What type of sensory receptor would likely respond to a green light?
ACTIVITY 3: The Action Potential: Threshold
15. In this lab simulation, what