ATI LPN
Exam Questions on Respiratory System Questions
Question 1 of 5
The apex of the heart is normally pointed
Correct Answer: B
Rationale: The heart's apex, its lower tip, points left of the midline, typically at the fifth intercostal space, reflecting its leftward tilt in the chest about two-thirds lie left of the sternum. Midline alignment is rare, as is rightward pointing (dextrocardia, a congenital anomaly). Gender doesn't alter this orientation is consistent. This leftward apex, formed by the left ventricle, aligns with the heart's pumping role, detectable in pulse checks, a key anatomical feature in physical exams and imaging, distinguishing normal from pathological positioning.
Question 2 of 5
Which term refers to the period of time during a cardiac cycle when contraction of a chamber occurs and pressure within the chamber rises?
Correct Answer: B
Rationale: Systole is the cardiac cycle phase when a chamber (atria or ventricles) contracts, raising pressure to eject blood ventricular systole pushes blood into the aorta/pulmonary trunk. Filling occurs during diastole, when chambers relax and fill. Repolarization is an electrical event, not a mechanical phase. Diastole is relaxation, opposite to contraction. Systole's pressure rise, peaking at ~120 mmHg in the left ventricle, drives circulation, a core concept in the cardiac cycle, critical in understanding blood flow dynamics and conditions like systolic dysfunction.
Question 3 of 5
What is the function of the foramen ovale during fetal life?
Correct Answer: A
Rationale: The foramen ovale, an atrial septal opening in fetuses, allows blood to flow from the right atrium to the left, bypassing lungs oxygen comes from the placenta via umbilical veins. Ventricular shunting isn't its role (ductus arteriosus does that). It's not a vena cava valve or aortic backflow preventer. This shunt, closing post-birth (fossa ovalis), optimizes fetal circulation, key in congenital defects like ASD where it persists, affecting oxygenation.
Question 4 of 5
The internal layer of tissue in the heart is the:
Correct Answer: D
Rationale: The endocardium, the heart's internal layer, is endothelium over connective tissue, lining chambers and contacting blood, distinct from epicardium (outer), myocardium (muscle), and pericardium (sac). It ensures smooth flow, key in endocarditis where infection targets it, a critical inner boundary in heart anatomy and pathology.
Question 5 of 5
The organ of the respiratory system where air is warmed, moistened and cleaned is the:
Correct Answer: A
Rationale: The nose (A) warms, moistens, and cleans air, per the key. Its turbinates increase surface area (150 cm²), warming air to 37°C, humidifying to 90%, and trapping particles via mucus/hairs (e.g., 10 μm filtered). The pharynx (B) conducts air/food, larynx (C) phonates, and trachea (D) conducts none match the nose's conditioning role. Physiology texts note nasal mucosa's vascularity and cilia clear 10000 L/day of air, distinguishing A from B's passageway, C's vocal function, or D's cartilage-supported conduit only the nose preps air for alveoli.