Cardiovascular System review questions from PPT

Question 1

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

Answer 1

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

Question 2

Describe the serous membrane lining the pericardial cavity.

Answer 2

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

Question 3

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

Answer 3

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

Question 4

Describe the heart’s location.

Answer 4

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

Question 5

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

Answer 5

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.

Question 6

List the arteries and veins of the coronary circulation.

Answer 6

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.

Question 7

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

Answer 7

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.

Question 8

Define mediastinum.

Answer 8

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.

Question 9

Why can cardiac tamponade be a life-threatening condition?

Answer 9

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

Question 10

Name the four cardiac chambers.

Answer 10

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

Question 11

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

Answer 11

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

Question 12

List the arteries and veins of the heart.

Answer 12

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.

Question 13

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

Answer 13

The coronary sinus.

Question 14

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

Answer 14

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

Question 15

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

Answer 15

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.

Question 16

Define cardiac regurgitation.

Answer 16

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

Question 17

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

Answer 17

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

Question 18

What do semilunar valves prevent?

Answer 18

Semilunar valves prevent the backflow of blood into the ventricles.

Question 19

Compare arteriosclerosis with atherosclerosis.

Answer 19

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.

Question 20

What prevents the AV valves from swinging into the atria?

Answer 20

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.

Question 21

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

Answer 21

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

Question 22

Describe the purpose of a stent.

Answer 22

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.

Question 23

Provide the alternate terms for heart contraction and heart relaxation.

Answer 23

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

Question 24

List the phases of the cardiac cycle.

Answer 24

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

Question 25

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

Answer 25

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.

Question 26

Define automaticity.

Answer 26

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

Question 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.

Answer 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.

Question 28

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

Answer 28

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.

Question 29

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

Answer 29

Rapid depolarization, plateau, and repolarization.

Question 30

Describe slow calcium channels and the significance of their activity.

Answer 30

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.

Question 31

Why does tetany not occur in cardiac muscle?

Answer 31

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.

Question 32

Compare bradycardia with tachycardia.

Answer 32

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

Question 33

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

Answer 33

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.

Question 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?

Answer 34

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.

Question 35

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

Answer 35

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.

Question 36

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

Answer 36

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).

Question 37

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

Answer 37

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.

Question 38

Define heart failure.

Answer 38

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

Question 39

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

Answer 39

SV= EDV-ESV, so

SV=125 mL-40 mL= 85 mL.

Question 40

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

Answer 40

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.

Question 41

Define electrocardiogram.

Answer 41

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

Question 42

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

Answer 42

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

Question 43

Why is ventricular fibrillation fatal?

Answer 43

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.

Question 44

List the factors that contribute to total peripheral resistance.

Answer 44

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

Question 45

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

Answer 45

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

Question 46

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

Answer 46

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.

Question 47

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

Answer 47

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.

Question 48

Define edema.

Answer 48

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

Question 49

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

Answer 49

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.

Question 50

Under what general conditions would fluid move into a capillary?

Answer 50

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

Question 51

Define tissue perfusion.

Answer 51

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

Question 52

Describe autoregulation as it pertains to cardiovascular function.

Answer 52

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

Question 53

Explain the function of baroreceptor reflexes.

Answer 53

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.

Question 54

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

Answer 54

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.

Question 55

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

Answer 55

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

Question 56

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

Answer 56

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.

Question 57

What is the function of chemoreceptor reflexes?

Answer 57

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

Question 58

Cite the locations of chemoreceptors.

Answer 58

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

Question 59

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

Answer 59

An increase in the respiratory rate reduces CO2 levels.

Question 60

Describe the respiratory pump.

Answer 60

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

Question 61

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

Answer 61

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

Question 62

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

Answer 62

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.

Question 63

Identify the compensatory mechanisms that respond to blood loss.

Answer 63

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.

Question 64

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

Answer 64

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

Question 65

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

Answer 65

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.