Cardiovascular System review questions from PPT Flashcards Preview

Anatomy & Physiology 2 > Cardiovascular System review questions from PPT > Flashcards

Flashcards in Cardiovascular System review questions from PPT Deck (65):
1

From superficial to deep, name the layers of the heart wall.

Layers of the Heart Wall. The heart wall is composed of three layers: the epicardium, myocardium, and endocardium. The superficial epicardium is the visceral layer of the serous pericardium

2

Describe the serous membrane lining the pericardial cavity.

the serous membrane of the pericardial cavity consists of 2 layers: visceral pericardium and parietal pericardium

3

Why is it important that cardiac tissue be richly supplied with mitochondria and capillaries?

Cardiac tissue is metabolically active and dependent on mitochondrial activity for ATP, obtaining oxygen and nutrients from local capillaries.

4

Describe the heart's location.

The heart is located within the pericardial sac in the anterior mediastinum, deep to the sternum and superior to the diaphragm.

5

Name and describe the shallow depressions and grooves found on the heart's external surface.

The anterior interventricular sulcus marks the boundary between the left and right ventricles on the heart's anterior surface; the shallower posterior interventricular sulcus marks the boundary between the left and right ventricles on the posterior surface; and the coronary sulcus is a deep groove that marks the border between the atria and the ventricles.

6

List the arteries and veins of the coronary circulation.

Arteries: left coronary artery, anterior interventricular artery, right coronary artery, marginal arteries, circumflex artery, and posterior interventricular artery. Veins: great cardiac vein, anterior cardiac veins, posterior cardiac vein, middle cardiac vein, and small cardiac vein.

7

Describe what happens to blood flow in the aorta during elastic rebound.

During elastic rebound, some blood in the aorta is driven forward into the systematic circuit, and some is forced back toward the left ventricle and into the coronary arteries.

8

Define mediastinum.

The mediastinum is the region between the two pleural cavities that contains the heart along with the great vessels (large arteries and veins attached to the heart), thymus, esophagus, and trachea.

9

Why can cardiac tamponade be a life-threatening condition?

Cardiac temponade can be a life-threatening condition because the accumulating fluid within the pericardial cavity restricts heart movement.

10

Name the four cardiac chambers.

The four cardiac chambers are the left atrium, right atrium, left ventricle, and right ventricle.

11

Which structures collect blood from the myocardium, and into which heart chamber does this blood flow?

Coronary veins collect blood from the myocardium and carry it to the right atrium.

12

List the arteries and veins of the heart.

Arteries: left coronary artery, anterior interventricular artery, right coronary artery, marginal arteries, circumflex artery, and posterior interventricular artery. Veins: great cardiac vein, anterior cardiac veins, posterior cardiac vein, middle cardiac vein, and small cardiac vein.

13

Identify the main vessel that collects venous blood from the myocardium.

The coronary sinus.

14

Damage to the semilunar valves on the right side of the heart would affect blood flow to which vessel?

Damage to the semilunar valve on the right side of the heart would affect blood flow to the pulmonary trunk.

15

Why is the left ventricle more muscular than the right ventricle?

The more muscular left ventricle must generate enough force to propel blood throughout the body (except the lungs), whereas the right ventricle must generate only enough force to propel blood the short distance to the lungs.

16

Define cardiac regurgitation.

Define cardiac regurgitation. Cardiac regurgitation is the back-flow of blood into the atria when the ventricles contract.

17

Compare the structure of the tricuspid valve with that of the pulmonary valve.

The tricuspid valve is composed of three relatively large flaps (cusps); the pulmonary valve is made up of three smaller half-moon-shaped cusps.

18

What do semilunar valves prevent?

Semilunar valves prevent the backflow of blood into the ventricles.

19

Compare arteriosclerosis with atherosclerosis.

Arteriosclerosis is any thickening an toughening of arterial walls; atherosclerosis is a type of arteriosclerosis characterized by changes in the endothelial lining and the formation of fatty deposits (plaque) in the tunica media.

20

What prevents the AV valves from swinging into the atria?

papillary muscles are muscles in the ventricles connected to the chordae tendinae. These muscles help stabilize the AV valves during ventricular contraction. chordae tendinae are fibrous cords that keep the AV valve cusps from swinging into the atria & prevent regurgitation of blood.

21

What is coronary ischemia, and what danger does it pose?

Coronary ischemia is a condition in which the blood supply of the coronary arteries has been reduced.

22

Describe the purpose of a stent.

Stents are artificial mesh "tubes" that prop open the natural blood vessel, creating a conduit to restore blood flow. Without adequate blood flow to the cardiac muscle, the tissue would die.

23

Provide the alternate terms for heart contraction and heart relaxation.

The alternate term for heart contraction is systole, and the term for heart relaxation is diastole.

24

List the phases of the cardiac cycle.

Atrial systole, atrial diastole, ventricular systole, and ventricular diastole.

25

Is the heart always pumping blood when pressure in the left ventricle is rising?

Is the heart always pumping blood when pressure in the left ventricle is rising? Explain. No. When pressure in the left ventricle first rises, the heart is contracting but blood is not leaving the heart. During this initial phase of contraction, called the period of isovolumetric contraction, both the AV valves and the semilunar valves are closed. The increase in pressure is the result of the cardiac muscle contracting. When the pressure in the ventricle exceeds that in the aorta, the aortic semilunar valves are forced open, and blood is rapidly ejected from the ventricle.

26

Define automaticity.

Automaticity is the ability of cardiac muscle tissue to contract without neural or hormonal stimulation.

27

If the cells of the SA node failed to function, how would the heart rate be affected? If the cells of the SA node failed to function, the heart would continue to beat, but at a slower rate; the AV node would act as the pacemaker.

If the cells of the SA node failed to function, how would the heart rate be affected? If the cells of the SA node failed to function, the heart would continue to beat, but at a slower rate; the AV node would act as the pacemaker.

28

Why is it important for impulses from the atria to be delayed at the AV node before they pass into the ventricles?

If the impulses from the atria were delayed at the AV node, they would be conducted through the ventricles so quickly by the bundle branches and Purkinje cells that the ventricles would begin contracting before the atria had finished contracting. As a result, the ventricles would not be as full of blood as they could be, and the pumping action of the heart would be less efficient.

29

List the three stages of an action potential in a cardiac muscle cell.

Rapid depolarization, plateau, and repolarization.

30

Describe slow calcium channels and the significance of their activity.

Slow calcium channels are voltage-gated calcium channels that open slowly and reamin open for a relatively long period--about 175 msec. When they are open, the entry of calcium ions into the sarcoplasm roughly balances the loss of positive ions through the active transport of sodium ions. As a result, the transmembrane potential remains near 0 mV for an extended period.

31

Why does tetany not occur in cardiac muscle?

Cardiac muscle has a long refractory period that continues until relaxation is well under way. As a result, another action potential cannot arrive quickly enough for summation to occur, and thus tetany cannot occur.

32

Compare bradycardia with tachycardia.

Bradycardia is a heart rate below 60 beats per minute; tachycardia is a heart rate above 100 beats per minute.

33

Describe the sites and actions of the cardioinhibitory and cardioacceleratory centers.

The cardioacceleratory center in the medulla oblongata activates sympathetic neurons to increase heart rate; the cardioinhibitory center (also in the medulla oblongata) controls the parasympathetic neurons that slow heart rate.

34

Caffeine has effects on conducting cells and contractile cells that are similar to those of NE. What effect would drinking large amounts of caffeinated beverages have on the heart rate?

Like NE, caffeine acts directly on the conducting system and contractile cells of the heart, increasing the rate at which they depolarize. Thus drinking large amounts of caffeinated beverages would increase the heart rate.

35

Define end-diastolic volume (EDV) and end-systolic volume (ESV).

The end-diastolic volume (EDV) is the amount of blood a ventricle contains at the end of diastole, just before a contraction begins; the end-systolic volume (ESV) is the amount of blood that remains at the end of ventricular systole.

36

What effect would an increase in venous return have on the stroke volume?

An increase in venous return would stretch the heart muscle. The more the heart muscle is stretched, the more forcefully it will contract (to a point). The more forceful the contraction, the more blood the heart will eject with each beat (stroke volume). Therefore, increased venous return would increase the stroke volume (if all other factors constant).

37

What effect would an increase in sympathetic stimulation of the heart have on the end-systolic volume (ESV)?

An increase in sympathetic stimulation of the heart would increase heart rate and force of contraction. The end-systolic volume (ESV) is the amount of blood that remains in a ventricle after a contraction (systole). The more forcefully the heart contracts, the more blood it ejects. Therefore, increased sympathetic stimulation should result in a lower ESV.

38

Define heart failure.

Heart failure is a condition in which the heart can no longer meet the oxygen and nutrient demands of peripheral tissues.

39

Compute Joe's stroke volume if his end-systolic volume (ESV) is 40 mL and his end-diastolic volume (EDV) is 125 mL.

SV= EDV-ESV, so
SV=125 mL-40 mL= 85 mL.

40

Why is it a potential problem if the heart beats too rapidly?

The amount of blood and heart pumps is proportional to the amount of blood that enters it. A heart that is beating too rapidly does not have adequate filling time, and it pumps less blood; peripheral tissues can be damaged by inadequate blood flow.

41

Define electrocardiogram.

An electrocardiogram (ECG or EKG) is a recording of the electrical activities of the heart over time.

42

List the important features of the ECG, and indicate what each represents.

The important features of an ECG are the P wave (atrial depolarization), the QRS complex (ventricular depolarization), and the T wave (ventricular repolarization).

43

Why is ventricular fibrillation fatal?

Ventricular fibrillation, which causes the condition known as cardiac arrest, it is fatal because ventricles merely quiver and do not pump blood into the systemic circulation.

44

List the factors that contribute to total peripheral resistance.

Total peripheral resistance reflects a combination of vascular resistance, vessel length, vessel diameter, blood viscosity, and turbulence.

45

Which would reduce peripheral resistance: an increase in vessel length or an increase in vessel diameter?

An increase in vessel diameter would reduce peripheral resistance. (An increase in vessel length increases peripheral resistance.)

46

Define blood flow, and describe its relationship to blood pressure and peripheral resistance.

Blood flow is the volume of blood flowing per unit of time through a vessel or group of vessels; it is directly proportional to blood pressure an inversely proportional to peripheral resistance.

47

In a healthy individual, where is blood pressure greater: in the aorta or in the inferior vena cava? explain.

In a healthy individual, blood pressure is greater at the aorta than at the inferior vena cava. If the pressure were higher in the inferior vena cava than in the aorta, blood would flow in the reverse direction.

48

Define edema.

Edema is an abnormal accumulation of interstitial fluid in peripheral tissues.

49

Identify the conditions that would shift the balance between hydro-static and osmotic forces.

Any condition that affects either blood pressure or osmotic pressures in the blood or tissues will shift the balance between hydro-static and osmotic forces.

50

Under what general conditions would fluid move into a capillary?

Fluid moves into a capillary whenever blood colloid osmotic pressure (BCOP) is greater than capillary hydrostatic pressure (CHP).

51

Define tissue perfusion.

Tissue perfusion is blood flow to tissues that is sufficient to deliver adequate oxygen and nutrients.

52

Describe autoregulation as it pertains to cardiovascular function.

Cardiovascular autoregulation involves local factors changing the pattern of blood flow within capillary beds in response to chemical changes in interstitial fluid.

53

Explain the function of baroreceptor reflexes.

Baroreceptor reflexes respond to changes in blood pressure. The baroreceptors- located in the walls of the carotid sinuses, aortic sinuses, and right atrium- monitor the degree of stretch at those sites.

54

Identify the hormones responsible for short-term regulation of declining blood pressure and blood volume.

Identify the hormones responsible for short-term regulation of declining blood pressure and blood volume. Epinephrine and norepinephrine from the adrenal medullae provide short-term regulation of declining blood pressure and blood volume.

55

List the hormones involved with the long-term response to declining blood pressure and blood volume.

Antidiuretic hormone (ADH), angiotensin II, erythropoietin (EPO), and aldosterone are hormones involved with the long-term response to declining blood pressure and blood volume.

56

In what way would a kidney respond to vasoconstriction of its renal artery?

Vasoconstriction of the renal artery would decrease both blood flow and blood pressure at the kidney. In response, the kidney would increase the amount of renin it releases, which in turn would increase the level of angiotensin II. The angiotensin II would bring about increased blood pressure and increased blood volume.

57

What is the function of chemoreceptor reflexes?

Chemoreceptor reflexes respond to changes in the pH, oxygen, or CO2 levels in the blood an cerebrospinal fluid (CSF).

58

Cite the locations of chemoreceptors.

Chemoreceptors are located in the carotid bodies, in the aortic bodies, and on the ventrolateral surfaces of the medulla oblongata.

59

What effect does an increase in the respiratory rate have on CO2 levels?

An increase in the respiratory rate reduces CO2 levels.

60

Describe the respiratory pump.

The respiratory pump is a mechanism by which a reduction of pressure in the thoracic cavity during inhalation assists venous return to the heart.

61

Describe the changes in cardiac output and blood flow during exercise.

During exercise, cardiac output increases, and blood flow to skeletal muscles increases at the expense of blood flow to less essential organs.

62

Why must blood flow to visceral organs be reduced during exercise?

Unless compensatory vasoconstriction occurs in nonessential organs, vasodilation in skeletal muscles would cause a potentially dangerous fall in blood pressure and blood flow throughout the body.

63

Identify the compensatory mechanisms that respond to blood loss.

Compensatory mechanisms that respond to blood loss include an increase in cardiac output, a mobilization of venous reserves, peripheral vasoconstriction, and the release of hormones that promote the retention of fluids and the maturation of erythrocytes.

64

Explain the role of aldosterone and ADH in the long-term restoration of blood volume.

Both aldosterone and ADH promote fluid retention and reabsorption by the kidneys, preventing further reductions in blood volume.

65

Name the immediate and long-term problems related to profuse blood loss

The immediate problem during hemorrhaging is the maintenance of adequate blood pressure and peripheral blood flow; the long-term problem is the restoration of normal blood volume.