ZOOL 2200: Quiz 8
Match each number on the figure below of an authorhythmic cell's action potential with what is occuring.
1.) Potassium channels slowly close and t-type calcium channels open 2.) L-type calcium channels open 3.) Voltage gated potassium channels open
Match the following parts of an ECG with their proper description.
P wave: atrial depolarization QRS complex: ventricular depolarization and atrial repolarization T wave: ventricular repolarization PQ segment: AV nodal delay QT segment: ventricular systole TQ interval: ventricular diastole
The wall of the left ventricle is much thicker than the wall of the right ventricle because:
the left ventricle pumps blood to the systemic circuit which is a high pressure circuit.
The cardiac contractile cells' action potentials have a plateau phase caused by:
the opening of calcium channels.
Which of the following is true of parasympathetic activity to the SA node?
T-Type calcium channel opening is decreased.
Match each phase of the cardiac with what is occuring.
Ventricular filling: AV valves are open and semilunar valves are closed Isovolumetric ventricular contraction: AV and semilunar valves are closed and the ventricles are in systole Ventricular ejection: semilunar valves are open and AV vales are closed Isovolumetric ventricular relaxation: AV and semilunar valves are closed and the ventricles are in diastole
Cardiac muscle differs from skeletal muscle in:
all of the above are found only in cardiac muscle.
The opening and closing of the atrioventricular valves are due to:
differences in pressure across the valves.
Stroke volume or the amount of blood pumped out of the ventricles per heart beat =
end diastolic volume - end systolic volume
Which of the following would DECREASE cardiac output?
increasing parasympathetic activity to the SA node.