Heart valves function to __________.

What is the physiological cause of a heart attack?

Blood leaves the inferior vena cava and flows directly into the __________.

Pressure is greatest in the ventricles when __________.

A recording of the electrical activity of a patient's heart shows that the atria are contracting regularly and normally, but every few beats the ventricles fail to contract. Which of the following is probably functioning improperly?

Your blood pressure is 120/70. The "120" indicates __________, and the "70" indicates __________.

When we compare the structures and functions of arteries and veins, we find that the walls of arteries are __________, the blood pressure inside arteries is __________, and the blood in arteries is moving __________ the heart.

Which of the following decreases blood pressure?