Cardiovascular System

If someone's heart has a stroke volume of 70 ml and a heart rate of 90 beats/min, the cardiac output equals _____________.

6.3L/min

The amount of blood pumped by one ventricle in one minute is called

Cardiac output

What happens to preload when there is venous constriction in the veins?

It increases

Which of the following is unique to cardiac muscle cells?

Only cardiac muscle is capable of autorhythmicity.

Which component of the heart conduction system would have the slowest rate of firing?

Purkinjee Fibers

Action potentials in myocardial cells have a characteristic plateau phase, which is caused primarily by the _________________.

Slow inward diffusion of Ca2+

Cardiac output is equal to�

Stroke volume x Cardiac Rate

Pacemakers may be useful in treating _____________.

a third degree AV node block

The first heart sound represents which portion of the cardiac cycle?

closing of the atrioventricular valves

The second heart sound results from vibrations generated by the ______________.

closing of the semilunar valves at the start of diastole

The preload acting on a ventricle is most equivalent to that chamber's _____________.

end-diastolic volume

The cardiovascular centers are located in which area of the brain?

medulla oblongata

Which of the following is not a broad area of function within the circulatory system?

neurochemical release

The semilunar valves _____________.

regulate the passage of blood from the ventricles into the pulmonary artery and the aorta

The Frank-Starling law of the heart describes the relationship between ___________.

stroke volume, end-diastolic volume, and contraction strength

Congenital septal defects are holes that form in the septum during the embryonic development of the heart---resulting in the abnormal flow of blood from _____________.

the left side of the heart to the right