Physioex exercise 3 activity 5. PhysioEx Exercise 5 Activity webapi.bu.edu 2022-11-03

Physioex exercise 3 activity 5 Rating: 4,5/10 1103 reviews

Physioex Exercise 3, Activity 5, is a laboratory simulation that allows students to investigate the effects of different concentrations of sodium ions on the action potential of a squid axon. This activity is designed to help students understand how changes in ion concentrations can affect the electrical activity of a neuron and how neurons communicate with one another.

In this activity, students first observe the action potential of a squid axon under normal conditions, with a sodium concentration of 145 millimoles per liter (mmol/L). They then manipulate the sodium concentration by adding or removing sodium ions from the solution surrounding the axon and observe the changes in the action potential.

One of the key findings of this activity is that increasing the concentration of sodium ions in the solution leads to an increase in the action potential. This is because increasing the concentration of sodium ions makes it easier for the sodium ions to flow into the axon through the sodium channels, leading to an increase in the depolarization of the membrane potential.

Conversely, decreasing the concentration of sodium ions in the solution leads to a decrease in the action potential. This is because decreasing the concentration of sodium ions makes it more difficult for the sodium ions to flow into the axon, leading to a decrease in the depolarization of the membrane potential.

Overall, this activity demonstrates the importance of ion concentrations in the regulation of neuronal activity and communication. It also highlights the role of ion channels in controlling the flow of ions into and out of the axon, which is essential for the generation and propagation of action potentials.

In summary, Physioex Exercise 3, Activity 5, is a valuable learning tool for students interested in understanding the mechanisms of neuronal communication and the role of ion concentrations and ion channels in this process. It provides a hands-on, interactive way for students to explore the effects of changes in ion concentrations on the action potential of a squid axon and to gain a deeper understanding of the fundamental principles of neuroscience.

PhysioEx Exercise 3 Activity webapi.bu.edu

physioex exercise 3 activity 5

What has happened to the nerve? Nerve Conduction Velocity Activity 8: Measuring Nerve Conduction Velocity 1. When voltage-gated Na+ channels between R1 and R2 are blocked with TTX, an action potential is still recorded at R1 because a. What are the physiological reasons for this relationship? There are voltage-gated Na+ channels all along the axon. This results from a change in membrane permeability first to Na then to K due to the opening of what type of ion channels? Do you see any kind of response on the oscilloscope screen? How does this tracing compare to the one that was generated at the threshold voltage? TTX alters the resting membrane potential of all neurons in the lips d. What sort of tracing is seen at the threshold voltage? Activity 3: Thermal Stimulation 1. What was the speed of the nerve? What explanation can you provide for this? The higher the voltage the more "excitable" the signal gets. Does this generate an action potential? It is slightly more "excited" than the threshold trace but less than the maximum trace.

Next

PhysioEx Exercise 3 Activity 5

physioex exercise 3 activity 5

Which of the following has the most negative voltage? It is the same as the threshold trace at 3. Does the hydrochloric acid generate an action potential? The result in conduction velocity depends on the size or diameter of the nerve. You would never get additional action potentials at this intensity. Voltage gated channels 2. You correctly answered: They are inversely proportional to each other. Increasing the flow tube length is analogous to increasing blood vessel length. It should immobilize the organism.

Next

SU_BIO_1012 Exercise 3 Activity 5_Green_webapi.bu.edu

physioex exercise 3 activity 5

Record this maximal voltage here: 4. You correctly answered: both friction and surface area. Activity 7: Testing the Effects of Lidocaine 1. When the stimulus frequency reaches a value beyond which no further increases in force are generated by the muscle, the muscle has reached its You correctly answered: a. Eating puffer fish can cause numbness of the lips, probably because a. No, it's the same.

Next

PhysioEx Exercise 5 Activity webapi.bu.edu

physioex exercise 3 activity 5

It is because one of the major physiological reasons of neurons is conductivity which is the ability to transmit the nerve impulse to other neurons, muscles, or glands. What was the speed of the nerve? Maybe it's caused by something else. Which of the following distinguishes a state of unfused tetanus from a state of complete fused tetanus?. Which nerve of the four has the fastest conduction velocity? How long does it take for the nerve to return to normal? Based on the results, what is your conclusion regarding the effects of myelination on conduction velocity? You correctly answered: changes in blood vessel diameter. Because of the heat on the bar the ions move faster than at room temperature.

Next

Physio Ex Exercise 5 Activity 3

physioex exercise 3 activity 5

The generation of an action potential uses voltage-gated Na+ channels. Action potentials propagate or remake themselves at each point along the axon. The action potential changes the membrane potential from -70 mV resting to +30 mV and back again to the resting membrane potential. Rat Nerve 2 4. Does the sodium chloride generate an action potential? What are the evolutionary advantages achieved by the myelination of neurons? Does this generate a trace? Elapsed time was 6. An action potential is a large, all-or-none change in membrane potential.

Next

PhysioEx Exercise 3 Activity 1

physioex exercise 3 activity 5

Your answer: The fluid flow rate will decrease. Submit this completed document by the assignment due date found in the Syllabus. Exercise 3: Neurophysiology of Nerve Impulses Worksheet Assignment Due: Week 4 Student instructions: Follow the step-by-step instructions for this exercise found in your text and record your answers in the spaces below. Muscle tension increases and decreases during a state of unfused tetanus. All of these are reasonable explanations. An action potential is generated when the membrane potential reaches threshold.


Next

Free Essay: Physioex 8 Exercise 3

physioex exercise 3 activity 5

What reason can you give for the change? It shouldn't elicit an action potential. Does this tracing differ from the original threshold stimulus tracing? What do you think would be the overall effect of Curare on the organism? You correctly answered: Blood vessel length is directly proportional to resistance and inversely proportional to blood flow. Which nerve in the group has the slowest conduction velocity? What explains this effect? How does this tracing compare with the other tracings you have generated? Both Sodium Chloride and Hydrochloric acid elicit an action potential. Because it prevents the sodium channels from opening. What is the relationship between nerve size and conduction velocity? What happens when the heated rod touches the nerve? Very similar except that it's peak is a little higher while it drops a little more as well. It produces a trace.

Next

physioex exercise 3 activity 5

You correctly answered: d. Just a flat line. It is harder to generate a second action potential soon after the first action potential because a. You correctly answered: The flow rate decreased. Does this tracing differ from the original threshold stimulus tracing? What sort of trace do you see? Why does Lidocaine have this effect on nerve fiber transmission? What was the threshold voltage, or the voltage at which you first saw an action potential? The ether stopped nerve fiber activity to function. Based on the lab, it seems that myelinated nerves have faster conduction velocity.

Next

physioex exercise 3 activity 5

The action potential is an all-or-none event. It prevents grave and debilitating conditions on the body. Stimulus frequency refers to You correctly answered: b. When the glass rod is touching the nerve, what do you see on the oscilloscope screen? Activity 4: Chemical Stimulation 1. How did this affect the flow rate? All of these answers are correct. In the control, the amplitudes of the action potentials at R1 and R2 are the same.

Next