Question 1

Closure of ductus arteriosus after birth occurs due to?

Accepted Answer

Answer reason: After birth, the first breaths expand the lungs and raise arterial oxygen tension, which directly promotes constriction of the ductus arteriosus smooth muscle. At the same time, placental removal decreases circulating prostaglandins (especially PGE2) that previously kept the ductus open. Therefore, increased oxygen tension is the key trigger for functional closure. The other options are incorrect because prostaglandins and low oxygen favor ductal patency rather than closure.

Question 2

The special muscle tissue Myocardium is found only in the?

Accepted Answer

Answer reason: Myocardium is the muscular middle layer of the heart wall composed of cardiac muscle tissue. Cardiac muscle is unique to the heart and is responsible for pumping blood through coordinated contractions. In contrast, the stomach contains smooth muscle, and the lung and brain do not contain myocardium as a tissue layer. Therefore, myocardium is found only in the heart.

Question 3

The heart is made up of which type of muscle-?

Accepted Answer

Answer reason: The myocardium (muscular layer of the heart wall) is composed of cardiac muscle, a specialized striated involuntary muscle. Cardiac myocytes have intercalated discs and gap junctions that allow coordinated electrical conduction and synchronized contraction. Skeletal muscle is voluntary and attached to bones, while smooth muscle lines hollow organs and blood vessels rather than forming the heart’s pumping tissue.

Question 4

The Gold standard investigation for congenital heart disease is?

Accepted Answer

Answer reason: Echocardiography is the first-line, noninvasive gold-standard test for diagnosing congenital heart disease because it directly visualizes cardiac anatomy (septal defects, valve abnormalities, outflow tract lesions) and assesses blood flow using Doppler. It provides real-time structural and hemodynamic information without radiation and can be performed at the bedside, including in neonates. Chest X-ray and ECG are supportive tests but cannot definitively define structural defects. Cardiac catheterization is invasive and is typically reserved for complex lesion delineation or therapeutic intervention rather than initial diagnosis.

Question 5

Normal Systolic blood pressure is?

Accepted Answer

Answer reason: Normal adult blood pressure is commonly referenced as approximately 120/80 mmHg, making 120 mmHg the standard normal systolic value. A systolic pressure of 80 mmHg would be abnormally low (hypotension), and 20 mmHg is not physiologically compatible with life. While some individuals may have a normal systolic near 110 mmHg, 120 mmHg is the classic textbook normal value tested in basic nursing/medical exams.

Question 6

The most common heart test is?

Accepted Answer

Answer reason: The electrocardiogram (ECG) is the most commonly used initial test for evaluating the heart because it is quick, noninvasive, widely available, and inexpensive. It provides immediate information about cardiac rhythm, conduction abnormalities, and evidence of ischemia or prior infarction. While echocardiography (USG) is also common, ECG is generally the most routine first-line heart test performed across settings. MRI and CT are specialized imaging studies used for specific indications rather than routine screening.

Question 7

The gold standard investigation for hypertension diagnosis is?

Accepted Answer

Answer reason: 24-hour ambulatory blood pressure monitoring (ABPM) is considered the gold standard for confirming a diagnosis of hypertension because it captures multiple readings during day and night. It helps identify white-coat hypertension and masked hypertension that can mislead office measurements. ABPM also provides nocturnal BP patterns (e.g., non-dipping), which are clinically relevant for cardiovascular risk assessment. ECG is useful for assessing end-organ effects (e.g., LVH) but does not diagnose hypertension.

Question 8

Tachycardia is a disorder of the?

Accepted Answer

Answer reason: Tachycardia refers to an abnormally fast heart rate (typically >100 beats/min in adults), which is a cardiac rhythm finding. It originates from altered electrical activity in the heart’s conduction system (e.g., sinus tachycardia or supraventricular/ventricular tachyarrhythmias). Therefore, it is a disorder of the heart rather than the kidneys, liver, or lungs.

Question 9

Which of the following heart sounds is best heard at the apex and is associated with left-sided heart failure?

Accepted Answer

Answer reason: An S3 (third heart sound) is classically best heard with the bell at the cardiac apex in the left lateral decubitus position and reflects increased ventricular filling/volume overload. In adults, an S3 is commonly associated with systolic dysfunction and congestive (left-sided) heart failure. S1 and S2 are normal heart sounds and are not specific for heart failure, while S4 is associated more with decreased ventricular compliance (e.g., LV hypertrophy) and is absent in atrial fibrillation.

Question 10

Which of the following is the primary pacemaker of the heart?

Accepted Answer

Answer reason: The sinoatrial (SA) node is the heart's primary pacemaker because it has the highest intrinsic rate of spontaneous depolarization, initiating each heartbeat. Its impulses spread through the atria and then reach the AV node for delayed conduction to the ventricles. The AV node, Bundle of His, bundle branches, and Purkinje fibers can act as secondary pacemakers if the SA node fails, but at slower intrinsic rates.

Question 11

Which blood vessel supplies oxygenated blood to heart muscle?

Accepted Answer

Answer reason: The myocardium (heart muscle) receives its oxygenated blood supply from the coronary arteries, which branch from the aorta just above the aortic valve. The pulmonary artery carries deoxygenated blood from the right ventricle to the lungs, and the pulmonary veins return oxygenated blood to the left atrium (not directly to the heart muscle). The jugular veins drain deoxygenated blood from the head and neck to the superior vena cava.

Question 12

Donated blood is taken from?

Accepted Answer

Answer reason: Whole blood donation is performed via venipuncture, typically accessing a superficial peripheral vein (e.g., median cubital vein) because it is low-pressure and safer to cannulate. Arterial puncture carries higher risk of bleeding, hematoma, and ischemic complications due to high pressure. Capillary sampling is only for small-volume tests, not donation, and blood is not taken directly from the heart in routine donation.

Question 13

Which condition is a congenital heart defect?

Accepted Answer

Answer reason: An atrial septal defect (ASD) is a structural opening in the interatrial septum that is present at birth, making it a congenital heart defect. Myocardial infarction is an acquired ischemic event due to coronary artery obstruction. Endocarditis and pericardial disease are typically acquired inflammatory/infectious conditions rather than congenital malformations.

Question 14

Blood pressure is the force exerted by blood on the walls of?

Accepted Answer

Answer reason: Blood pressure refers to the pressure of circulating blood against the walls of the arteries, which is what is measured with a cuff (e.g., brachial artery). Arteries have thicker, more muscular walls and carry blood under higher pressure from the heart compared with veins and capillaries. Veins are low-pressure capacitance vessels, and capillary pressures are much lower and not what standard “blood pressure” typically denotes. Therefore, the best answer is arteries.

Question 15

Which of organic continuously works (24 hours)?

Accepted Answer

Answer reason: The heart contracts continuously to pump blood and maintain circulation and blood pressure throughout the day and night. Unlike sense organs such as the eye and nose, the heart does not have routine voluntary “rest” periods compatible with life. While the brain remains active, the classic single-best answer in basic physiology for an organ that works continuously is the heart due to its nonstop pumping requirement.

Question 16

A 4-year-old child presents with a continuous "machine-like" murmur. What is the most likely diagnosis?

Accepted Answer

Answer reason: A continuous “machine-like” murmur is classic for patent ductus arteriosus (PDA) due to persistent flow from the aorta to the pulmonary artery throughout systole and diastole. ASD typically causes a fixed split S2 with a systolic ejection murmur, and VSD usually produces a harsh holosystolic murmur. Tetralogy of Fallot is associated with cyanosis and a systolic ejection murmur from pulmonary stenosis rather than a continuous murmur.

Question 17

Which organ continuously works (24 hours)?

Accepted Answer

Answer reason: The heart must contract continuously to maintain cardiac output and systemic perfusion; stopping even briefly leads to rapid loss of consciousness and organ injury. While the brain is always metabolically active, the item typically tests the unique continuous mechanical pumping function required for life. Nose and eye do not function continuously in the same vital, nonstop manner.

Question 18

A person with BP 140/90 mm Hg or above is considered to have?

Accepted Answer

Answer reason: A blood pressure of 140/90 mm Hg or higher meets traditional diagnostic cutoffs for hypertension (e.g., older JNC criteria and commonly taught nursing fundamentals thresholds). It indicates chronically elevated systolic and/or diastolic pressure, which increases cardiovascular risk over time. The other options do not match this BP level: hypotension is abnormally low BP, normal BP is lower than this range, and pulse rate is a separate vital sign from blood pressure.

Question 19

Impure blood (deoxygenated)carried by?

Accepted Answer

Answer reason: Deoxygenated (impure) blood is carried from the right ventricle to the lungs via the pulmonary artery for oxygenation. In contrast, the aorta carries oxygenated blood from the left ventricle to systemic circulation. Coronary arteries supply the myocardium with oxygenated blood, and pulmonary veins uniquely return oxygenated blood from the lungs to the left atrium.

Question 20

Which valve prevents backflow of blood from right ventricle to right atrium?

Accepted Answer

Answer reason: The tricuspid valve is the right atrioventricular (AV) valve located between the right atrium and right ventricle. It closes during right ventricular systole to prevent regurgitation of blood back into the right atrium. The mitral valve is the left AV valve, while the aortic and pulmonary valves are semilunar valves that prevent backflow from the great arteries into the ventricles.

Question 21

What's the most common cause of stroke?

Accepted Answer

Answer reason: Most strokes are ischemic, and the most common underlying mechanism is atherosclerotic disease causing thrombosis or artery-to-artery embolization (large-artery atherosclerosis). Hypertension is a major risk factor for both ischemic and hemorrhagic stroke, but it is not itself the direct “cause” as often as atherosclerotic plaque-related occlusion. Atrial fibrillation is an important cause of cardioembolic stroke but accounts for a smaller proportion overall than atherosclerotic mechanisms. Vasculitis is a relatively uncommon cause of stroke.

Question 22

Which of the following can cause heart attack?

Accepted Answer

Answer reason: Elevated cholesterol, especially LDL, contributes to atherosclerotic plaque formation in coronary arteries. Plaque rupture with subsequent thrombus formation can acutely occlude a coronary vessel, causing myocardial infarction (heart attack). While abnormal blood sugar is a risk factor over time (via diabetes/vascular disease), cholesterol is the most directly implicated single factor among the listed choices. Blood urea and blood protein are not primary direct causes of heart attack in standard pathophysiology framing.

Question 23

Which vein carries deoxygenated blood from heart to lungs?

Accepted Answer

Answer reason: Deoxygenated blood leaves the right ventricle and travels to the lungs through the pulmonary arteries for oxygenation. Pulmonary veins carry oxygenated blood from the lungs back to the left atrium, so they are not correct here. Coronary veins drain deoxygenated blood from the myocardium into the right atrium, and jugular veins drain the head and neck into the superior vena cava.

Question 24

Which organ of the body never rest?

Accepted Answer

Answer reason: The heart must continuously pump blood to deliver oxygen and nutrients and remove metabolic waste from tissues. A prolonged pause in cardiac activity leads rapidly to loss of perfusion and death, so it is considered an organ that "never rests" during life. While the brain remains active even during sleep, its activity level changes and it can enter rest states, unlike the continuous requirement for effective cardiac pumping.

Question 25

What is the innermost layer of the heart wall called?

Accepted Answer

Answer reason: The endocardium is the innermost layer of the heart wall and directly lines the heart chambers and valves. It provides a smooth surface that helps prevent turbulence and thrombus formation. By contrast, the myocardium is the muscular middle layer responsible for contraction, and the epicardium is the outer layer (visceral pericardium).

Question 26

The leading cause of death worldwide due to NCDs is?

Accepted Answer

Answer reason: Globally, cardiovascular diseases (especially ischemic heart disease and stroke) account for the largest proportion of deaths among noncommunicable diseases. Road traffic accidents are not NCDs and are categorized as injuries. Chronic respiratory diseases and diabetes are major NCD contributors but cause fewer deaths overall than cardiovascular disease. Therefore, cardiovascular diseases are the leading cause of death worldwide due to NCDs.

Question 27

What is the normal blood pressure range for an adult?

Accepted Answer

Answer reason: A normal adult blood pressure is commonly taught as approximately 120/80 mmHg (systolic/diastolic). Values such as 140/90 mmHg and 160/100 mmHg meet criteria for hypertension in many guidelines, not normal. A reading of 100/60 mmHg can be normal for some individuals but is generally considered on the low-normal side rather than the standard reference value. Therefore, 120/80 mmHg is the best answer.

Question 28

The ductus arteriosus connects?

Accepted Answer

Answer reason: In fetal circulation, the ductus arteriosus is a vascular shunt that diverts blood from the pulmonary artery into the aorta, bypassing the nonfunctioning fetal lungs. This allows most right ventricular output to enter systemic circulation. After birth, increased oxygen tension and reduced prostaglandins promote functional closure, forming the ligamentum arteriosum.

Question 29

Which rhythm is shockable during cardiac arrest?

Accepted Answer

Answer reason: In adult cardiac arrest, the shockable rhythms are ventricular fibrillation (VF) and pulseless ventricular tachycardia; defibrillation is indicated to terminate these disorganized ventricular rhythms and allow an organized rhythm to resume. Asystole and pulseless electrical activity (PEA) are non-shockable rhythms managed with high-quality CPR and epinephrine while searching for reversible causes. Atrial fibrillation is typically a perfusing rhythm and is not treated with defibrillation in the cardiac arrest algorithm.

Question 30

Which of the following structures is the primary pacemaker of the heart?

Accepted Answer

Answer reason: The sinoatrial (SA) node has the highest intrinsic firing rate (about 60–100 impulses/min) and therefore sets the normal heart rhythm. The atrioventricular (AV) node (about 40–60/min) and the Purkinje/ventricular pacemakers (about 15–40/min) serve as backup pacemakers if the SA node fails. Because the fastest pacemaker dominates, the SA node is the primary pacemaker.

Question 31

Why do many patients with very high heart rates frequently have chest pain and shortness of breath?

Accepted Answer

Answer reason: At very high heart rates, diastole shortens disproportionately, and coronary arteries primarily perfuse the myocardium during diastole. Less diastolic time reduces coronary perfusion and myocardial oxygen delivery while demand is simultaneously increased from the faster rate. This supply–demand mismatch can cause myocardial ischemia, presenting as chest pain and dyspnea. The other options do not explain the physiologic mechanism of ischemic symptoms in tachycardia.

Question 32

Which of the following is the most likely complication of inferior wall myocardial infarction (MI)?

Accepted Answer

Answer reason: Inferior wall MI typically involves the right coronary artery, which often supplies the sinoatrial (SA) and atrioventricular (AV) nodes. Ischemia to these conduction tissues predisposes to sinus bradycardia and varying degrees of AV block (bradydysrhythmias). In contrast, cardiogenic shock is more characteristic of large anterior MIs, and ventricular rupture is a mechanical complication more associated with transmural infarcts (often anterior/lateral). Tachydysrhythmias can occur with MI but are less specifically linked to inferior wall involvement than bradyarrhythmias.

Question 33

Which clinical sign is most suggestive of cardiac tamponade in a trauma patient?

Accepted Answer

Answer reason: Cardiac tamponade classically presents with Beck’s triad: hypotension, jugular venous distension, and muffled heart sounds due to impaired ventricular filling from pericardial fluid under pressure. In trauma, this obstructive shock pattern is a key distinguishing feature from other causes of shock. The other options include findings that are nonspecific or inconsistent with tamponade (e.g., bounding pulses/hypertension, bradycardia).

Question 34

A nurse is assessing a child who has a ventricular septal defect. Which of the following findings should the nurse expect?

Accepted Answer

Answer reason: A ventricular septal defect produces a left-to-right shunt that creates turbulent systolic flow across the interventricular septum, classically heard as a holosystolic murmur at the left lower sternal border. Small VSDs may have a louder murmur, while larger defects can have softer murmurs but still localize to the left sternal border. Cyanosis is not expected with an uncomplicated VSD unless Eisenmenger physiology develops later. Widened pulse pressure is more typical of patent ductus arteriosus or aortic regurgitation rather than VSD.

Question 35

For STEMI pt, maximum goal time for ED door-to-balloon-inflation time for PCI?

Accepted Answer

Answer reason: For an acute STEMI treated with primary PCI, the evidence-based performance goal is a door-to-balloon (first device/balloon inflation) time of 90 minutes or less. Shorter reperfusion times are strongly associated with reduced infarct size and lower mortality. The other time options exceed recommended targets and would represent delayed reperfusion.

Question 36

Heart beat less than 60 beats/minute is regarded as?

Accepted Answer

Answer reason: In adults, a heart rate below 60 beats per minute is defined as bradycardia. Tachycardia refers to an elevated heart rate (commonly >100/min). Hypotension and hypertension describe low and high blood pressure, respectively, not heart rate.

Question 37

The normal blood pressure is?

Accepted Answer

Answer reason: Normal adult blood pressure is commonly defined as a systolic pressure

Question 38

Which of the following heart valves has two cusps?

Accepted Answer

Answer reason: The mitral (bicuspid) valve is the left atrioventricular valve and has two cusps (anterior and posterior leaflets). In contrast, the tricuspid valve has three cusps. The aortic and pulmonary valves are semilunar valves and typically have three cusps each. Therefore, the valve with two cusps is the mitral valve.

Question 39

Which blood vessel carries oxygen-rich blood to liver?

Accepted Answer

Answer reason: The hepatic artery supplies the liver with oxygenated (oxygen-rich) blood from the systemic circulation via the celiac trunk. The portal vein carries nutrient-rich but relatively deoxygenated blood from the gastrointestinal tract to the liver. Hepatic veins drain blood from the liver into the inferior vena cava rather than supplying it. The renal artery supplies the kidneys, not the liver.

Question 40

The walls of left ventricles are thicker to facilitate?

Accepted Answer

Answer reason: The left ventricle pumps oxygenated blood through the aorta to the entire body, which requires generating high pressure to overcome systemic vascular resistance. To produce this higher pressure, the left ventricular myocardium is thicker than the right ventricle. The right ventricle only pumps to the low-resistance pulmonary circulation, so it does not need as much muscle mass. Therefore, the thicker left ventricular wall facilitates systemic circulation.

Question 41

Blood pressure is measured in units of?

Accepted Answer

Answer reason: Blood pressure is traditionally expressed as the height of a mercury column, so the standard unit is millimeters of mercury (mm Hg). Although pressure can be expressed in SI units (e.g., pascals, N/m²), clinical blood pressure readings are reported as systolic/diastolic values in mm Hg. °F measures temperature, and beats per minute measures heart rate, not pressure.

Question 42

Deep vein thrombosis occurs in ...?

Accepted Answer

Answer reason: Deep vein thrombosis (DVT) most commonly forms in the deep veins of the lower extremities, especially the calf and proximal leg veins (e.g., popliteal/femoral). Venous stasis, endothelial injury, and hypercoagulability (Virchow triad) promote clot formation in these dependent veins. Upper extremity and abdominal/pelvic venous thromboses occur but are less common than leg DVT in typical presentations.

Question 43

The size of the human heart is approximately equal to?

Accepted Answer

Answer reason: In adults, the heart’s size is commonly approximated as about the size of the person’s clenched fist, which is a standard anatomical teaching aid. The brain, liver, and stomach are substantially larger organs than the heart. This comparison helps convey the heart’s overall dimensions without needing measurements.

Question 44

Which of the following is not a component of the cardiovascular system?

Accepted Answer

Answer reason: The cardiovascular system consists of the heart, blood vessels, and blood, which together circulate oxygen, nutrients, and wastes throughout the body. The lungs are part of the respiratory system and are responsible for gas exchange (oxygenation and removal of carbon dioxide). Although the heart and lungs function closely together in pulmonary circulation, the lungs are not considered a component of the cardiovascular system itself.

Question 45

Which ECG change is seen in hypokalemia?

Accepted Answer

Answer reason: Hypokalemia delays ventricular repolarization and classically produces prominent U waves on the ECG, often accompanied by ST depression and flattened T waves. Tall peaked T waves are more typical of hyperkalemia. ST elevation suggests acute myocardial injury (e.g., STEMI or pericarditis), and pathologic Q waves indicate prior myocardial infarction rather than a potassium abnormality.

Question 46

Mitral valve prolapse is most commonly found in what body type?

Accepted Answer

Answer reason: Mitral valve prolapse classically occurs in individuals with a slender (asthenic) habitus and is more common in young, thin females, though it can occur in any body type. This association is also seen in connective-tissue phenotypes (e.g., Marfan-like features), which often present as tall and thin. The other body-type options do not reflect the typical epidemiologic association described for MVP. Therefore, the best answer is tall and thin individuals.

Question 47

In human heart blood returning from lungs first drains into the ?

Accepted Answer

Answer reason: Oxygenated blood returns from the lungs to the heart through the pulmonary veins. These veins empty directly into the left atrium, which then passes blood to the left ventricle through the mitral valve. The right-sided chambers primarily handle deoxygenated blood returning from the body and pumping it to the lungs.

Question 48

Chest pain at rest, transient ST elevation, normal cardiac enzymes?

Accepted Answer

Answer reason: Chest pain occurring at rest with transient ST-segment elevation and normal cardiac enzymes is classic for Prinzmetal (variant) angina due to episodic coronary vasospasm. The ST elevation resolves when the spasm resolves and does not produce myocardial necrosis, so troponins/enzymes remain normal. Unstable angina typically causes ST depression or T-wave inversion rather than ST elevation, and NSTEMI would have elevated cardiac biomarkers. GERD can mimic chest pain but does not produce transient ischemic ST elevation.

Question 49

What is the normal heart rate for an adult?

Accepted Answer

Answer reason: A normal resting adult heart rate is typically defined as 60–100 beats per minute. Rates below 60 bpm may be normal in well-conditioned athletes but are not the standard reference range for the general adult population. The higher ranges (100–140 and 140–180 bpm) reflect tachycardia and are more consistent with infants/children or physiologic stress in adults. Therefore, 60–100 bpm is the best answer.

Question 50

Bleeding from artery is characterized by which of the following?

Accepted Answer

Answer reason: Arterial bleeding is typically bright red and spurts in synchrony with the heartbeat due to higher intraluminal pressure, making the flow appear pulsatile rather than steady. This pulsatile spurting can be described as intermittent compared with the more continuous, steady flow seen with venous bleeding. Color options here are not discriminating because both arterial and venous blood are generally red (venous is darker, not purple). Therefore, the best characterization among the given options is intermittent bleeding.

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