Module 2
Signals leave the AV node and descend along this structure toward the apex
AV bundle
Which of the following belong to the pulmonary circuit
Pulmonary arteries and pulmonary veins
The pulmonary circuit is supplied by what side of the heart?
Right side (right ventricle)
The pacemaker that determines the heart rate
Sinuatrial (SA) node
Distributes the electrical excitation to the ventricles
Subendocardial conducting network (Purkinje fibers)
Why is cardiac muscle not prone to fatigue
it makes little use of anaerobic fermentation or the oxygen debt mechanism
The plateau in the action potential of cardiac muscle results from the action of _________
slow Ca2+ channels
The electrical gateway to the ventricles
Atrioventricular (AV) node
The long plateau in the action potential observed in cardiomyocytes is probably related with ________ staying longer in the cytosol
Ca2+
Place the following vessels in the order through which blood would pass, beginning with blood entering the systemic circuit after exiting the heart
Conducting arteries > distributing arteries > resistance arteries > Arterioles > Capillaries > Post-capillary venules > Muscular venules > Medium venules > Venous sinuses > Large veins
Which vessels have the thickest tunic media
Large arteries
Atrial depolarization causes the ___________
P wave
Opening and closing of the heart valves is caused by __________
Pressure gradients
Which of the following is a feature shared by cardiac muscle and skeletal muscle
muscle fiber striations
Blood usually passes through one network of capillaries from the time it leaves the heart until the time it returns, but there are exceptions, notably the __________
portal systems and anastomoses
