Download 6. Cardiovascular Worksheet Part I

CARDIOVASCULAR SYSTEM WORKSHEET
The Cardiovascular System Consists of the Heart and Blood Vessels (p. 458)
1. An artery is:
2. A vein is:
3. How is an Atrium different from a Ventricle?
4. The pulmonary circuit can be described as going from the _________ ventricle to the _________ atrium.
5. The systemic circuit can be described as going from the _________ ventricle to the _________ atrium.
CARDIAC MUSCLE AND THE HEART - The Heart Has Four Chambers
6. Name 3 functions of the fibroskeleton surrounding the openings to major arteries and chambers. (Fig. 14-9)
1)
2)
3)
7. What is mitral valve stenosis? What can it result in?
8. What is AV valve prolapse? What can it result in?
Cardiac Muscle Cells Contract without Nervous Stimulation
9. About 1% of myocardiocytes are __________________________________________________________.
The heart can contract without connections to other parts of the body, because the signal is _____________,
meaning that it is ________________________________________________________________________.
Excitation-Contraction (EC) Coupling in Cardiac Muscle is Similar to Smooth and Skeletal Muscle
10. In cardiac muscle, an AP also initiates EC coupling, but the AP originates spontaneously in the hearts
pacemaker cells and spreads into the contractile cells through _____________________________________.
11. The ryanodine receptors are Ca2+ channels and opening them causes _____________________________.
12. The Ca2+ released from the SR provides about ________ of the Ca2+ needed for muscle contraction.
13. In cardiac muscle, when cytoplasmic Ca2+ concentrations decrease, what happens to the muscle?
14. What are the two ways that Ca2+ is removed from the cytoplasm of cardiac muscle cells?
1)
2)
15. For the Na+-Ca2+ antiport protein, _____ Ca2+ moves _______ cell for every _____ Na+ moving ______.
2
Cardiac Muscle Contraction can be Graded
16. The force generated by cardiac muscle is proportional to the number of crossbridges that are active. The
number of active crossbridges is determined by ________________________________________________.
17. What happens to cardiac muscle when it is stretched? ________________________________________.
Myocardial Contractile Cells
18. In the contractile myocardiocytes the resting membrane potential is about _________.
19. The depolarization phase is caused by: ____________________________________________________.
20. The plateau phase is caused by: __________________________________________________________.
21. The repolarization phase is caused by: ____________________________________________________.
Myocardial Autorhythmic Cells
22. From Fig. 14-15, note that the membrane potential is not stable, but fluctuates from _______mV to
______ mV (which is threshold for these cells). At threshold, Ca2+ _______ the cell at even greater amounts.
23. The depolarization phase is caused by: ____________________________________________________.
24. The repolarization phase is caused by: ____________________________________________________.
The Heart as a Pump
25. From Fig. 14-18 (p. 478), list the order of the electrical conduction in the heart.
26. Which of the areas listed above is the normal Pacemaker of the heart? ___________________________.
The Heart Contracts and Relaxes Once during the Cardiac Cycle
27. Diastole is:
28. Systole is:
1) The heart at 'rest': Atrial and ventricular diastole (Fig. l4-24)
29. Is the heart in atrial and ventricular systole at the same time during this phase? ________.
30. When both the atria and ventricles are relaxing: Which valves are open? _________________________.
31. Is blood flowing into the heart? _____. Which chambers? _____________________________________.
2) Completion of ventricular filling: Atrial systole
32. In a person at rest, how much of ventricular filling depends on atrial contraction? __________________.
33. What wave or wave segment on the ECG is associated with this phase? __________________________.
3
3) Early ventricular contraction and the first heart sound
34. What electrical event precedes ventricular systole? ___________________________________________.
35. As the ventricles contract, why do the AV valves close? ______________________________________.
36. What creates the heart sounds? __________________________________________________________.
37. Explain what is happening during isovolumetric ventricular contraction.
38. What happens to pressure in the ventricles during isovolumetric ventricular contraction? ____________.
4) The heart pumps: ventricular ejection
39. Why do the semilunar valves open, allowing blood to be ejected into the arteries?
40. If blood flows out of the ventricles, then ventricular pressure must be (lower/higher?) than arterial
pressure.
5) Ventricular diastole and the second heart sound
41. As the ventricles relax, the ventricular pressure (increases/decreases?).
42. Why do the semilunar valves close? _____________________________________________________.
43. When do the AV valves open? __________________________________________________________.
Stroke Volume is the Volume of Blood Pumped by one Ventricle in one Contraction
44. Define stroke volume. (Give units!) _______________________________________________________
45. How do you calculate stroke volume? _____________________________________________________
46. If the EDV increases and the ESV decreases, has the heart pumped more or less blood?
Cardiac Output is a Measure of Cardiac Performance
46. Define cardiac output (CO). (Give units!) __________________________________________________
47. Give average values for stroke volume and CO in a man weighing 70 kg while at rest:
Heart Rate is Modulated by Autonomic Neurons and Catecholamines
48. Explain the antagonistic control of heart rate by sympathetic and parasympathetic neurons. (Fig. 14-28)
49. Name the parasympathetic and sympathetic neurotransmitters and their receptors at the SA node.
Multiple Factors Influence Stroke Volume
50. Stroke volume is directly related to the _____________ generated by cardiac muscle during contraction.