Theme 3. Studying of electric effects in excitable tissues. Membran potentials (mp), action potentials (ap).

Questions for Speech and Test Control.

1. The excitable tissues, their characteristics.

2. Irritability, excitability as the main tissues reactions on irritating. The excitation.

3. The modern notions about the structure and functions of the cellular membranes.

4. The ionic canals of the membranes, their species and functions. The ionic pumps of the membranes, their functions.

5. The receptors of the membranes, their functions.

6. The membranous potential of rest (MPR or RP), the origin mechanisms, the registration methods, the RP parameters and the RP physiologic role.

7. The action potential (AP), the origin mechanisms, the registration methods, the AP phases, the AP parameters, the AP physiologic role.

8. Changes of the cell excitability during the development of the AP. Periods of the absolute and relative refractority, mechanisms of its origin, the physiologic importance.

9. The local response (LP). The critical level of depolarization. The threshold of depolarization as the measure of the excitability.

Questions for Written Answer.

1. Draw the MPR scheme of an excitable cell.

2. Draw the AP scheme of single-phase process, mark the AP phases, their duration.

3. Draw the scheme of the AP phases and the cell excitability phases correlations

4. Characterize the phases of the absolute and the relative refractority and the supernormal excitability.

5. Characterize the level of metabolic processes in an excitable cell during excitation.

6. Describe the potassium balance potential.

7. Describe the modern methods of the MPR registration.

Curriculum of the Practical Studies.

1. Review of the film about the experiments on registering the electric potential of the excited tissues.

2. Studying the influence of the AP of the frog skeletal muscle in the tetanus state on the nerve of the second neuromuscular frog preparation (the experiment of the second Time tetanus).

3. Studying the influence of the AP of the frog heart on the nerve of the neuromuscular preparation.

Theme 4. Investigation of electric irritation methods of neural and muscular fibers.

Questions for Speech and Test Control.

1. The direct current action on the excitable tissues. Using in the clinical practice.

2. The change of the membrane potential in the electric current action as the irritant.

3. Dependence of a stimulus threshold strenght on its duration.

4. Dependence of a stimulus threshold strenght on the stepness of its growth.

5. Dependence of a stimulus threshold strenght on the moment of opening or closing the electric circuit.

Questions for Written Answer.

1. Write classification of the types of irritation.

2. List the advantages of the electric stimulation methods.

3. List main effects the direct current action on the excitable tissues.

4. Draw the curve and describe the mechanism of Hoorweg-Weiss-Lapicque law.

5. Describe the mechanism of accomodation phenomenon.

6. Draw the curve and describe the mechanism of MP change at the moment of opening or closing the electric circuit.

Curriculum of the Practical studies.

1. Review and discuss the film about the cell stimulation by electric current.