0. Segment representing the time heart muscle is electrically silent 18. Waveform representing total ventricular SYSTOLE 19. Repolarization of the atria is found within which wave 20. Firing of the AV node occurs at the apex of which wave 19. Repolarization of the atria is found within which wave 20. Firing of the AV node occurs at the apex of which wave

Why is the delay in electrical conduction between the atria and the ventricles important? Tachycardia results if the delay is absent. Atria must contract to fill the ventricles with blood. AV valves must have time to close slowly. Bradycardia results if the delay is absent.

40. The period of ejection:   A. begins with closure of the AV-valves and ends with opening of the AV-valves B. begins with opening of the aortic valve and ends with closure of the aortic valve C. begins with the P-wave and ends with the QRS-complex D. begins with the QRS-complex and ends with the T-wave

5.    This is not and will not be graded

The intrinsic heart rate is established by Sympathetic innervation of the SA node Autorhythmic cells in the AV node O The End Systolic Volume Autorhythmic cells in the SA node The End Diastolic Volume

Can you help with number 1 and 2   This is not and will not be graded

1) A drug was applied to a person that blocked the pore/channel in the L-type calcium channel in cardiac muscle cells. The drug had no other effects. True/false: Cross-bridge cycling and tension production would occur normally in drug-treated fibers. 2) The plateau phase of a cardiac action potential is an absolute refractory period.True/false 3) If a heart lacked gap junctions, an organ-level contraction would occur.True/false 4) During a pacemaker potential, what is caused in neighboring muscle fibers when threshold potential is reached. Group of answer choices a)cross-bridge cycling b)Receptor potential c)An action potential d)A graded potential

1. In figure ( bottom left): use the barorecptor reflex to explain why the R-R interval increases as systolic pressure (SBP) increases. 2. In figure ( bottom right): explain why the slope of SBP change to the R-R interval change.

Define the term 'distributive shock' and briefly explain why two of the three types of distributive shock result in increased heart rate, whilst the third type results in decreased heart rate.

Select TRUE or FALSE to best describe the statements below, relating the events of the cardiac cycle. Keep in mind that these events may be chemical, electrical and mechanical. atrial pressure is greater than ventricular pressure while semilunar valves are оpen ventricular pressure is greater than atrial pressure when the atrioventricular valves are closed atrioventricular valves are open during ventricular emptying the end diastolic volume of the ventricles is reached before ventricles contract 1 ventricular filling occurs before depolarization of the atria 1 atrioventricular valves and 1. TRUE 1 semilunar valves are closed at the beginning of ventricular systole 2. FALSE end systolic volume increases when more blood empties from the ventricles the greatest pressure is reached in the ventricles while they are emptying the right atrium depolarizes before the left atrium ventricular depolarization occurs during the T-wave semilunar valves are open during ventricular filling ventricular…