signal along nerves to the This node is located in the right atrium. An electrical signal is sent and causes the The signal is received by the node in the heart. the This signal causes corresponds to the the ECG. This node sends a signal to through the this corresponds to of the ECG. node located in the right atrium. hormone of the septum and to in the walls of the There is a slight delay before the next heartbeat as the dissipates from the heart. This corresponds to the and of of the ECG. The sympathetic nervous system causes an heart rate due to the hormone The parasympathetic nervous system causes a heart rate due to the

Which of the following are false about the inward rectifier? OA The inward rectifier current is carried by potassium OB. The inward rectifier carries inward current at potentials negative to the Nersnst potential for potassium under voltage clamp conditions. OC. The inward rectifier current obeys Ohm's law. OD. The inward rectifier is absent in the sino-atrial node. OE All of the above are true.

Which of the following would increase mean arterial pressure (MAP) ? Group of answer choices An increase in sympathetic activity An increase in arteriolar diameter A reduction in heart rate A reduction in cardiac output

The semilunar valves prevent blood from moving: Group of answer choices from the atria back into the veins. from the ventricles back into the atria. from the arteries back into the ventricles. moving backward in the capillaries. moving backward in the arteries.

choose the correct statement about gap junctions: allows the atria to be excited simultaneously and does the same for the ventricles, Tightly join cardiac cells so they do not separate during contraction, responsible for setting intrinsic heart rate

Why does blood keep flowing through the vascular system even during diastole? Valves in veins maintain blood flow throughout the cardiac cycle Pressure built up in arterial walls during systole allows large arteries to squeeze blood downstream even during diastole O Arterial walls have a low elasticity Blood doesn't flow through our vascular system during diastole Blood flows into vasculature only during systole

isovolumetric contraction isovolumetric relaxation ventricular filling ventricular ejection closed rises S1 drops depolarize S2 The first phase of the cardiac cycle is . This is when a lot of blood is in the atria, which causes atrial pressure to be higher than the ventricles. The atrioventricular valves open, and blood moves from the atria to the ventricles. At the end of this phase, the atria contract to maintain pressure and blood flow into the ventricles. As blood leaves the atria, the pressure in the atria As blood enters the ventricles, the pressure in the ventricles Towards the end of this phase, the pressure in the ventricles will exceed the pressure in the atria. At this point, the heart enters the second phase of the cardiac cycle: At this point, the AV valves shut, and we hear . The atria repolarize and the ventricles (due to the QRS complex of the ECG), causing ventricular contraction. Although contracting, it is not yet moving blood into the arteries. All 4 heart valves…

The cardiac action potential is substantially longer than a neuron potential due to: spontaneous depolarization Ca++ entry gap junctions myocardial contractility

A patient has a condition in which the SA node is no longer functioning. The atrioventricular (AV) node is now setting the pace and rhythm for the heart. What difference would you expect to see in the ECG of this patient? Group of answer choices P wave would be much larger than normal there would continue to be a normal sinus rhythm QRS complex would be absent the rhythm would be slower

which of the following is the first to occur during the period of ventricular systole? QRS complex, sharp rise and ventricular pressure, or blood leaving the ventricle.