The pulmonary arteries carry deoxygenated blood from the right ventricle to the lungs.
Correct Answer
True
True. The pulmonary circuit reverses the usual pattern: its arteries carry deoxygenated blood to the lungs, and its veins bring oxygenated blood back to the left atrium.
Category: Blood Flow and Vessels
Question 2
The pulmonary valve lies between the left ventricle and the pulmonary artery.
Correct Answer
False
False. The pulmonary valve lies between the right ventricle and the pulmonary artery. The valve between the left ventricle and the aorta is the aortic valve.
Category: Heart Anatomy
Question 3
Fluid between the parietal and visceral layers of the pericardium reduces friction as the heart beats.
Correct Answer
True
True. The serous pericardium has two layers with a thin film of fluid between them, letting the heart move smoothly within its sac.
Category: Heart Anatomy
Question 4
Arteries carry blood toward the heart, and veins carry blood away from it.
Correct Answer
False
False. Arteries carry blood away from the heart and branch into arterioles and capillaries, while veins return blood to the heart. Direction, not oxygen content, defines the vessel type.
Category: Blood Flow and Vessels
Question 5
Sympathetic stimulation by epinephrine and norepinephrine increases myocardial contractility.
Correct Answer
True
True. Sympathetic stimulation strengthens each contraction and raises stroke volume. Elevated calcium and inotropic drugs also increase contractility.
Category: Cardiac Output
Question 6
Veins have thick muscular walls that pump blood back to the heart without help from surrounding muscles.
Correct Answer
False
False. Venous pressure is low, so blood returns to the heart with the help of surrounding skeletal muscle contraction, and one-way valves in the veins prevent backflow.
Category: Blood Flow and Vessels
Question 7
Blood pressure rises when either cardiac output or systemic vascular resistance increases.
Correct Answer
True
True. Mean arterial pressure equals cardiac output times systemic vascular resistance, so raising either one raises pressure. Antihypertensive drugs lower pressure by reducing one or both.
Category: Blood Pressure Regulation
Question 8
The superior and inferior venae cavae return blood from the body to the left atrium.
Correct Answer
False
False. The venae cavae empty deoxygenated blood into the right atrium. The left atrium receives oxygenated blood from the pulmonary veins.
Category: Blood Flow and Vessels
Question 9
Atrial repolarization is not seen as a separate wave on a standard ECG.
Correct Answer
True
True. Atrial repolarization happens at the same time as ventricular depolarization, so it is hidden within the much larger QRS complex.
Category: ECG Basics
Question 10
An ECG lead records a downward deflection when electrical current flows toward it.
Correct Answer
False
False. Current moving toward a lead produces an upward deflection, and current moving away produces a downward deflection.
Category: ECG Basics
Question 11
In an irregularly irregular rhythm, the time between beats varies with no identifiable pattern.
Correct Answer
True
True. An irregularly irregular rhythm has no repeating pattern, whereas a regularly irregular rhythm varies in a predictable pattern.
Category: ECG Basics
Question 12
Gap junctions block the spread of depolarization from one cardiac muscle cell to the next.
Correct Answer
False
False. Gap junctions are channels that connect neighboring cardiac cells and let depolarization spread rapidly from cell to cell, so the muscle contracts as a unit.
Category: Cardiac Action Potential
Question 13
Calcium entering a cardiac muscle cell during the action potential triggers release of more calcium from the sarcoplasmic reticulum.
Correct Answer
True
True. This calcium-induced calcium release works through ryanodine receptors on the sarcoplasmic reticulum and supplies most of the calcium needed for contraction.
Category: Cardiac Action Potential
Question 14
Hypotension can reduce perfusion of vital organs, so the nurse checks blood pressure before giving drugs that lower it.
Correct Answer
True
True. Blood pressure must be high enough to keep blood flowing to the brain, heart and kidneys. Many cardiovascular drugs lower it further, so the nurse checks it before each dose and reports a low reading as the prescriber's parameters direct.
Category: Blood Pressure Regulation
Question 15
A regular rhythm from the sinoatrial node at 120 beats per minute falls within normal sinus rhythm.
Correct Answer
False
False. Normal sinus rhythm has a rate of 60 to 100 beats per minute. A sinus rhythm faster than 100 is tachycardia.
Category: Conduction System
Question 16
The coronary arteries branch off the aorta just above the aortic valve.
Correct Answer
True
True. The right and left coronary arteries arise from the base of the aorta. Plaque that narrows them causes ischemia and can lead to myocardial infarction.
Category: Blood Flow and Vessels
Question 17
Capillaries have thick, muscular walls that limit exchange between blood and tissues.
Correct Answer
False
False. Capillaries have very thin walls, which allow oxygen, nutrients and wastes to pass between blood and tissues.
Category: Blood Flow and Vessels
Question 18
Stroke volume is the volume of blood a ventricle ejects with each contraction.
Correct Answer
True
True. Stroke volume is the amount pumped per beat, and multiplying it by heart rate gives cardiac output. Preload, afterload and contractility all change stroke volume.
Category: Cardiac Output
Question 19
Myocardial ischemia increases the strength of ventricular contraction.
Correct Answer
False
False. Ischemia deprives heart muscle of oxygen and decreases contractility. Sympathetic stimulation, elevated calcium and inotropic drugs are what increase it.
Category: Cardiac Output
Question 20
A segment on an ECG includes at least one waveform.
Correct Answer
False
False. A segment is the flat stretch between two waves and contains no waveform. An interval includes a waveform plus a segment, such as the PR or QT interval.
Category: ECG Basics