 |
| 1 | |
The amount of blood pumped by one ventricle in one minute, is called the |
| | A) | stroke volume |
| | B) | end-diastolic volume |
| | C) | ejection fraction |
| | D) | cardiac output |
|
|
|
| 2 | |
If someone's heart has a stroke volume of 70 ml and a heart rate of 90 beat/minute, the cardiac output would be |
| | A) | 6.3 L/min |
| | B) | 0.77 L/min |
| | C) | 70 ml/min |
| | D) | 1.28 ml/min |
|
|
|
| 3 | |
The sinoatrial node depolarizes more frequently under the influence of |
| | A) | norepinephrine. |
| | B) | acetylcholine. |
| | C) | the vagus nerve. |
| | D) | the medulla oblongata. |
|
|
|
| 4 | |
Any mechanism that increases heart rate is said to have a positive ____ effect. |
| | A) | feedback |
| | B) | chronotropic |
| | C) | inotropic |
| | D) | cholinergic |
|
|
|
| 5 | |
Stroke volume is regulated by all of the following except |
| | A) | end-diastolic volume. |
| | B) | cardiac output. |
| | C) | contractility. |
| | D) | peripheral resistance. |
|
|
|
| 6 | |
The preload acting on a ventricle is equivalent to that chamber's |
| | A) | contractility |
| | B) | stroke volume |
| | C) | end-diastolic volume |
| | D) | ejection fraction |
|
|
|
| 7 | |
The afterload imposed on a ventricle refers to |
| | A) | its end-systolic volume, the blood left after contraction is complete. |
| | B) | the amount of blood added to a ventricle by atrial systole. |
| | C) | the total peripheral resistance opposing the ejection of blood. |
| | D) | the ejection fraction, or percentage of EDV ejected by ventricular systole. |
|
|
|
| 8 | |
Contraction of the left ventricle of the heart at rest normally expels about ____ of the blood contained in the chamber. |
| | A) | 10-15% |
| | B) | 25-33% |
| | C) | 60-70% |
| | D) | 98-100% |
|
|
|
| 9 | |
The Frank-Starling law of the heart describes the proportional relationship between |
| | A) | stroke volume and cardiac output. |
| | B) | stroke volume and end-diastolic volume. |
| | C) | stroke volume is and total peripheral resistance. |
| | D) | the left and right ventricles. |
|
|
|
| 10 | |
The contractility of a muscle fiber is its |
| | A) | contraction strength at any length. |
| | B) | contraction strength at a particular fiber length. |
| | C) | contraction frequency, which determines heart rate. |
| | D) | ability to contract, which is restored after the refractory period. |
|
|
|
| 11 | |
A positive inotropic agent is something that |
| | A) | reduces the heart rate in positive feedback loop. |
| | B) | increases the heart rate in positive feedback loop. |
| | C) | increases the contractility of myocardial fibers. |
| | D) | decreases the contractility of myocardial fibers. |
|
|
|
| 12 | |
Veins are said to have a higher ____ than arteries because they stretch more easily and a higher ____ because they contain more blood. |
| | A) | compliance; capacitance |
| | B) | capacitance; compliance |
| | C) | elasticity; capacitance |
| | D) | elasticity; compliance |
|
|
|
| 13 | |
The colloid osmotic pressure of blood plasma is due to its high concentration of ____. |
| | A) | albumin |
| | B) | hemoglobin |
| | C) | sodium |
| | D) | glucose |
|
|
|
| 14 | |
If the hydrostatic pressure (P) of the blood in a capillary is 19 mmHg and that of the tissue fluid is 1mmHg, while the colloid osmotic pressure (p) of the blood is 23 mmHg and that of the tissue fluid is 0 mmHg, at this particular portion of the capillary fluid is being __________with a net force of __________. |
| | A) | given off; 5 mmHg |
| | B) | given off; -3 mmHg |
| | C) | taken up; 3 mmHg |
| | D) | taken up; -5 mmHg |
|
|
|
| 15 | |
According to the classic view of the Starling forces, capillaries usually tend to absorb fluid |
| | A) | at the arteriolar end. |
| | B) | at the venular end. |
| | C) | only when the precapillary sphincters are open. |
| | D) | at neither end; they filter fluid, and it is up to the lymphatic vessels to absorb it. |
|
|
|
| 16 | |
Edema could be caused by all of the following except |
| | A) | high arterial blood pressure (hypertension) |
| | B) | leakage of plasma proteins into the tissue fluid, as in inflammation and allergy |
| | C) | an elevated level of albumin in the blood plasma |
| | D) | an obstruction of the lymphatic drainage |
|
|
|
| 17 | |
Myxedema is a disease caused by hypothyroidism, which causes production of excessive amounts of glycoprotein in the interstitial spaces. The effect of this on capillary fluid dynamics would be to cause |
| | A) | precapillary sphincters to shut off blood flow to affected tissues. |
| | B) | vasodilation of the capillaries. |
| | C) | increased filtration and accumulation of fluid in the tissues resulting in edema. |
| | D) | increased transfer of tissue fluid into the bloodstream, resulting in hypertension. |
|
|
|
| 18 | |
Elephantiasis is caused by |
| | A) | the bite of a specific tick. |
| | B) | nematode worm parasite. |
| | C) | blood albumin deficiency. |
| | D) | allergy to elephants. |
|
|
|
| 19 | |
Secretion of antidiuretic hormone would |
| | A) | stimulate fluid retention by the kidneys. |
| | B) | stimulate sodium retention . |
| | C) | accelerate the heartbeat. |
| | D) | cause vasoconstriction. |
|
|
|
| 20 | |
Osmoreceptors regulating the release of ADH are found in the |
| | A) | kidneys. |
| | B) | right atrium of the heart. |
| | C) | aortic arch and carotid sinuses. |
| | D) | hypothalamus. |
|
|
|
| 21 | |
Low blood pressure stimulates the secretion of the mineralocorticoid |
| | A) | aldosterone. |
| | B) | angiotensin II. |
| | C) | vasopressin (ADH). |
| | D) | atrial natriuretic peptide (ANP). |
|
|
|
| 22 | |
The enzyme that converts angiotensinogent to angiotensin I, is |
| | A) | rennin. |
| | B) | angiotensin-converting enzyme (ACE). |
| | C) | atrial natriuretic peptide (ANP). |
| | D) | vasopressin (ADH). |
|
|
|
| 23 | |
Production of angiotensin II would |
| | A) | cause vasodilation of arterioles and muscular arteries. |
| | B) | inhibit the sense of thirst. |
| | C) | stimulate excretion of excess sodium by the kidneys. |
| | D) | raise the blood pressure. |
|
|
|
| 24 | |
Atrial natriuretic hormone helps to lower blood pressure and is secreted by the |
| | A) | hypothalamus. |
| | B) | kidneys. |
| | C) | adrenal cortex. |
| | D) | heart. |
|
|
|
| 25 | |
Blood will not flow unless there is a sufficient DP between point A and point B in the circulatory system. In this sentence DP represents |
| | A) | colloid osmotic pressure in the plasma. |
| | B) | plasma protein concentration. |
| | C) | hydrostatic pressure difference. |
| | D) | an osmotic gradient. |
|
|
|
| 26 | |
In the proportionality expression R µ Lη / r4, R represents the total force that resists the flow of blood from point A to point B, and L represents the |
| | A) | systolic pressure generated by the heart. |
| | B) | viscosity of the blood. |
| | C) | radius of a blood vessel. |
| | D) | length of a blood vessel. |
|
|
|
| 27 | |
Of all the factors that can affect blood flow to a particular tissue, the most effective and easiest to control from moment to moment, is |
| | A) | vessel radius. |
| | B) | blood viscosity. |
| | C) | vessel length. |
| | D) | pressure differential. |
|
|
|
| 28 | |
Intrinsic control of blood flow refers to the |
| | A) | way in which blood flow is determined by cardiac output. |
| | B) | blood flow in all places other than the heart itself. |
| | C) | control of blood flow by metabolic products of the tissues. |
| | D) | control of blood flow by the nervous and endocrine systems. |
|
|
|
| 29 | |
During exercise or stress, the sympathetic nervous system causes vasodilation in the skeletal muscle but vasoconstriction in the skin. It is able to achieve these opposite effects because |
| | A) | sympathetic fibers secrete epinephrine in the muscle and acetylcholine in the skin. |
| | B) | bradykinin stimulates constriction of arterioles in the dermis. |
| | C) | the muscles have cholinergic sympathetic fibers and the skin has adrenergic fibers. |
| | D) | the muscles have α-adrenergic receptors and the skin has β-adrenergic receptors. |
|
|
|
| 30 | |
Autoregulation of the blood vessels means essentially the same thing as ____ regulation. |
| | A) | extrinsic |
| | B) | intrinsic |
| | C) | myogenic |
| | D) | neurogenic |
|
|
|
| 31 | |
Vasodilation is often caused by |
| | A) | increase in oxygen concentration in the tissue fluid. |
| | B) | decrease in carbon dioxide concentration in the tissue fluid. |
| | C) | increase in pH of the tissue fluid. |
| | D) | decrease in K+ concentration in the tissue fluid. |
|
|
|
| 32 | |
During systole, the ventricular myocardium gets its oxygen supply mainly from |
| | A) | hemoglobin. |
| | B) | myoglobin. |
| | C) | its high density of blood capillaries. |
| | D) | its high density of mitochondria. |
|
|
|
| 33 | |
Coronary arteries must dilate during exercise to meet the heart's increased oxygen demand. This occurs under the influence of all of the following compounds, except |
| | A) | carbon dioxide |
| | B) | potassium |
| | C) | adenosine |
| | D) | acetylcholine |
|
|
|
| 34 | |
During exercise the cardiac output may rise to five times the resting value. In most people this is due mainly to an increase in |
| | A) | stroke volume. |
| | B) | ejection fraction. |
| | C) | end-diastolic volume. |
| | D) | heart rate. |
|
|
|
| 35 | |
Athletes trained for endurance, such as swimmers and marathon runners, have a higher stroke volume at rest mainly because they have |
| | A) | resting bradycardia. |
| | B) | more sympathetic stimulation of the SA node. |
| | C) | increased heart rate. |
| | D) | decreased end-diastolic volume. |
|
|
|
| 36 | |
Arteriovenous anastomoses are found mainly in the |
| | A) | dermis of the skin. |
| | B) | mesenteries of the abdominal cavity. |
| | C) | cerebral circulation. |
| | D) | renal circulation. |
|
|
|
| 37 | |
____ is a polypeptide vasodilator produced by the sweat glands. |
| | A) | Bradykinin |
| | B) | Histamine |
| | C) | Serotonin |
| | D) | Endorphin |
|
|
|
| 38 | |
The sympathoadrenal system can raise blood pressure by |
| | A) | stimulating vasodilation of the arterioles |
| | B) | promoting a positive chronotropic effect on the heart |
| | C) | promoting a negative inotropic effect on the heart |
| | D) | dilating renal arteries and reducing urine output |
|
|
|
| 39 | |
Baroreceptors are specialized pressure receptors found in the |
| | A) | vena cava. |
| | B) | descending aorta. |
| | C) | medulla oblongata. |
| | D) | aortic arch. |
|
|
|
| 40 | |
Cardiac output may drop when one goes from a lying to a standing position because of |
| | A) | the baroreceptor reflex. |
| | B) | venous pooling. |
| | C) | orthostatic hypertension. |
| | D) | sinus tachycardia. |
|
|
|
| 41 | |
Stretch receptors in the left atrium help control blood pressure by |
| | A) | inducing the heart rate |
| | B) | stimulating sodium retention |
| | C) | stimulating production of more ADH |
| | D) | causing decreased urine output |
|
|
|
| 42 | |
The auscultatory method is used for |
| | A) | correcting orthostatic hypotension. |
| | B) | reducing tachycardia. |
| | C) | restoring blood volume. |
| | D) | measuring blood pressure. |
|
|
|
| 43 | |
A severe infection could decrease blood pressure by causing |
| | A) | cardiogenic shock. |
| | B) | anaphylactic shock. |
| | C) | septic shock. |
| | D) | hypovolemic shock. |
|
|
|
| 44 | |
A bee sting is most likely to cause |
| | A) | cardiogenic shock. |
| | B) | anaphylactic shock. |
| | C) | septic shock. |
| | D) | hypovolemic shock. |
|
|
|
| 45 | |
Pulmonary edema, shortness of breath, and fatigue are most likely to result from |
| | A) | cardiogenic shock. |
| | B) | anaphylactic shock. |
| | C) | right-sided congestive heart failure. |
| | D) | left-sided congestive heart failure. |
|
|
|
| 46 | |
____ stimulates the heart by inhibiting cardiac membrane Na+/K+ pumps and ultimately raising the intracellular Ca2+ concentration in the myocardium. |
| | A) | Epinephrine |
| | B) | Nitroglycerin |
| | C) | Digitalis |
| | D) | Methyldopa |
|
|
.