Mastering Cariovasc Flashcards
Arteries are most accurately defined as blood vessels that carry ________
blood away from the heart
A patient is given a β1 receptor agonist. What would you expect to find?
Increased heart rate and increased cardiac output
Choose the correct order in which blood would make contact with the following structures as it traveled from the left atrium through the blood vessels and back to the right atrium.
1) Abdominal aorta
2) Ascending arteries
3) Inferior vena cava
4) Hepatic artery
5) Superior vena cava
6) Left ventricle
7) Ascending veins
6, 1, 4, 7, 3
As blood flows away from the heart, how does overall blood pressure in vessels change? Why?
Blood pressure decreases, because of the effects of friction between the vessel walls and the moving blood.
Why does the pressure in the arteries and arterioles fall as the blood moves away from the heart?
Friction causes a loss of energy
Which of the following causes a decrease in resistance in a vessel?
Vasodilation
What is an advantage to the longer duration of cardiac action potential compared with the skeletal muscle action potential?
The longer duration prevents tetanus, which allows the heart chambers to relax and refill with blood before the next contraction.
What is the role of heart valves?
Heart valves ensure one-way flow of blood through the heart chambers.
n a cardiac autorhythmic cell, which ion is responsible for the increase in membrane potential from threshold during an action potential?
Ca2+
Which cells act as the heart’s pacemaker? Why are they the pacemaker cells?
Cells of the SA node are the usual pacemakers, because they are autorhythmic cells, and set the pace of the heart rate.
In a laboratory, students used a stimulus that decreased the distance between R waves on an ECG. This represents a ____
decreased length of time for one heartbeat and increased heart rate
