Preview

Exercise 3: Neurophysiology of Nerve Impulses

Powerful Essays
Open Document
Open Document
1413 Words
Grammar
Grammar
Plagiarism
Plagiarism
Writing
Writing
Score
Score
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

You May Also Find These Documents Helpful

  • Satisfactory Essays

    Nt1310 Unit 3 Lab Report

    • 405 Words
    • 2 Pages

    The threshold for the second action potential increased as the interval between the stimuli decreased as predicted.…

    • 405 Words
    • 2 Pages
    Satisfactory Essays
  • Satisfactory Essays

    Nt1310 Unit 3 Quiz

    • 315 Words
    • 2 Pages

    3. Explain what is happening in regards to sodium and potassium in a neuron at (see figure 7.10)…

    • 315 Words
    • 2 Pages
    Satisfactory Essays
  • Good Essays

    1. Define graded potential. How does your data show that stimulation of the olfactory receptor is graded?…

    • 979 Words
    • 4 Pages
    Good Essays
  • Powerful Essays

    NeuroPhsioEX 3

    • 592 Words
    • 3 Pages

    Electrical, mechanical, thermal, and chemical stimulation are all capable of generating an action potential in a nerve.…

    • 592 Words
    • 3 Pages
    Powerful Essays
  • Satisfactory Essays

    6. If the level of the odor-producing chemicals dissolved in the mucus surrounding the olfactory cilia reaches a threshold, a receptor potential and then an action potential will be generated and passed to the olfactory nerves in the olfactory bulb.…

    • 427 Words
    • 2 Pages
    Satisfactory Essays
  • Powerful Essays

    Unit 9 Assignment SC121

    • 907 Words
    • 9 Pages

    a. Values of maximal depolarization of membrane potential (mV) at different stimulation voltages, by location.…

    • 907 Words
    • 9 Pages
    Powerful Essays
  • Good Essays

    Neurons are the only living cells that maintain a difference in the concentration of ions across their membranes.…

    • 10962 Words
    • 62 Pages
    Good Essays
  • Satisfactory Essays

    Physio 9.0

    • 613 Words
    • 3 Pages

    Post-lab Quiz Results You scored 0% by answering 0 out of 4 questions correctly. 1. What happened when you increased the amount of ATP dispensed with the same concentration of sodium and potassium on either side of the membrane? Your answer: c. The ions were transported more slowly. Correct answer: b. More ions were transported. 2. At what concentration of ATP were the sodium and potassium maximally transported? Your answer: b. 1 mM ATP Correct answer: d. 3 mM ATP 3. What was the effect of adding more Na+ -K+ pumps to the simulated cell? Your answer: b. More ions were transported in 60 minutes. Correct answer: a. Transport of the ions was faster. 4. Describe the…

    • 613 Words
    • 3 Pages
    Satisfactory Essays
  • Powerful Essays

    The sensory end of this nerve is less specialized. 76. Why didn't the Pacinian corpuscle respond to high-intensity light? Light-transducing proteins are not present in the Pacinian corpuscle. 77.…

    • 2586 Words
    • 11 Pages
    Powerful Essays
  • Powerful Essays

    Physioex 3

    • 950 Words
    • 4 Pages

    Discuss the relative permeability of the membrane to Na+ and K+ in a resting neuron.…

    • 950 Words
    • 4 Pages
    Powerful Essays
  • Good Essays

    Unit nine

    • 1541 Words
    • 6 Pages

    a. Describe how there can be an electrical change on either side of a membrane thereby generating a membrane potential. The membrane potential is due to the presence of an ionic concentration difference and electrical gradient between both sides of the membrane.movement of charged molecules across the cellular membrane leads to the creation of electrical signals.…

    • 1541 Words
    • 6 Pages
    Good Essays
  • Satisfactory Essays

    c. The increase in K+ concentration reduces the ratio of intracellular to extracellular potassium and decreases the resting membrane potential, making it more positive and closer to threshold potential. The action potential required for contraction is made easier to reach and over-stimulation of muscle cells by neurons cause muscle cramping and fatigue.…

    • 405 Words
    • 2 Pages
    Satisfactory Essays
  • Powerful Essays

    Action Lab Simulations

    • 1622 Words
    • 7 Pages

    C. Sodium conductance has a sharp spike (almost vertical line to a steady decline, reaching a top of approximately 0.034), however potassium (which peaks at 0.013) is a gentle rise and decline. Sodium conductance peaks at the same time as the membrane voltage. The potassium conductance begins to increase at about 0mV. The sodium conductance begins to increase at -34mV. Sodium movement is much higher at the beginning. Potassium is gradual from middle to end.…

    • 1622 Words
    • 7 Pages
    Powerful Essays
  • Better Essays

    Physio Ex 8

    • 4569 Words
    • 19 Pages

    eurons have two major physiological properties: excitability, or the ability to respond to stimuli and convert them into nerve impulses, and conductivity, the ability to transmit an impulse (in this case, to take the neural impulse and pass it along the cell membrane). In the resting neuron (that is, a neuron that does not have any neural impulses), the exterior of the cell membrane is positively charged and the interior is negatively charged relative to the outside. This difference in electrical charge across the plasma membrane is referred to as the resting membrane potential, and the membrane is said to be polarized. The sodium-potassium pump in the membrane maintains the difference in electrical charge established by diffusion of ions. This active transport mechanism moves 3 sodium ions (Na ) out of the cell while moving in 2 potassium ions (K ). Therefore, the major cation (positively charged ion) outside the cell in the extracellular fluid is Na , and the major cation inside the cell is K . The inner surface of the cell membrane is more negative than the outer surface, mainly due to intracellular proteins, which, at body pH, tend to be negatively charged. The resting membrane potential can be measured…

    • 4569 Words
    • 19 Pages
    Better Essays
  • Satisfactory Essays

    My a and P

    • 313 Words
    • 2 Pages

    What will happen to the resting membrane potential of an excitable cell if: (Write pos or neg to indicate which way the membrane potential would change.)…

    • 313 Words
    • 2 Pages
    Satisfactory Essays

Related Topics