Question 1

Which of the following best describes the function of Type II alveolar cells in the lungs?

Accepted Answer

They synthesize and secrete pulmonary surfactant to reduce surface tension.

Question 2

A patient with cystic fibrosis has thick, sticky mucus in their airways. This is primarily due to a mutation in which gene, and what is the physiological consequence?

Accepted Answer

Mutation in the CFTR gene, leading to decreased Cl- secretion and impaired mucociliary clearance.

Question 3

During normal inspiration, which of the following pressure relationships is true?

Accepted Answer

$$P_{alv} \u003c P_{atm}$$

Question 4

Which of the following best explains why carbon monoxide (CO) poisoning is so dangerous?

Accepted Answer

CO binds to hemoglobin with a much higher affinity than oxygen, preventing oxygen transport.

Question 5

A coal worker develops pulmonary fibrosis after years of exposure to coal dust. Which of the following best describes the pathophysiology?

Accepted Answer

Fibrous connective tissue replaces normal lung tissue, reducing lung compliance and gas exchange.

Question 6

Which of the following equations correctly represents the reaction catalyzed by carbonic anhydrase in red blood cells?

Accepted Answer

$$CO_2 + H_2O$$ \rightarrow H_2CO_3 \rightarrow $$HCO_3^- + H$$^+$$

Question 7

A patient with emphysema has fewer and larger alveoli. What is the primary consequence of this change?

Accepted Answer

Decreased surface area for gas exchange, leading to hypoxemia.

Question 8

Which of the following best describes the Bohr effect in hemoglobin-oxygen binding?

Accepted Answer

A decrease in pH (increase in $$H^+) $$lowers hemoglobin's affinity for $$O_2$$, promoting oxygen unloading in tissues.

Question 9

Which of the following is a characteristic finding in obstructive pulmonary disorders such as asthma or COPD?

Accepted Answer

Reduced FEV$$_1$$ with normal or near-normal vital capacity.

Question 10

A person ascends rapidly from a deep dive and develops joint pain and dizziness. What is the most likely cause?

Accepted Answer

Nitrogen bubbles forming in the blood due to rapid decompression (decompression sickness).

Question 11

Which of the following best explains why fetal hemoglobin (HbF) is able to extract oxygen from maternal blood?

Accepted Answer

HbF has a higher affinity for $$O_2$$ because it does not bind $$2,3-$$DPG as strongly as adult hemoglobin.

Question 12

A patient with sickle cell anemia experiences a pain crisis after intense exercise. Which of the following best explains this phenomenon?

Accepted Answer

Deoxygenated hemoglobin S polymerizes, distorting RBCs and blocking capillaries.

Question 13

Which of the following best describes the role of the dorsal respiratory group (DRG) in the medulla oblongata?

Accepted Answer

It generates the basic rhythm of inspiration by sending signals to the diaphragm.

Question 14

Which of the following is the primary mechanism for $$CO_2$$ transport in the blood?

Accepted Answer

As bicarbonate ion ($$HCO_3$$^-$$) in plasma.

Question 15

A patient with chronic bronchitis has a productive cough for more than 3 months in 2 consecutive years. Which of the following best explains the underlying pathology?

Accepted Answer

Chronic inflammation and mucus hypersecretion in the bronchi.

Question 16

Which of the following best describes the effect of hypoxia on pulmonary arterioles?

Accepted Answer

They constrict to divert blood flow away from poorly ventilated areas.

Question 17

Which of the following is the correct order of airflow through the respiratory tree, starting from the trachea?

Accepted Answer

Primary bronchi → Secondary bronchi → Terminal bronchioles → Respiratory bronchioles → Alveolar ducts → Alveolar sacs

Question 18

A patient with asthma experiences bronchoconstriction after exposure to an allergen. Which immune cells and mediators are primarily responsible for the early phase of this response?

Accepted Answer

IgE-activated mast cells releasing prostaglandins and leukotrienes.

Question 19

Which of the following best explains why the mucociliary escalator is impaired in cystic fibrosis?

Accepted Answer

Decreased chloride secretion leads to thick, sticky mucus that cannot be cleared by cilia.

Question 20

Which of the following best describes the effect of 2,3-DPG (2,3-diphosphoglycerate) on hemoglobin?

Accepted Answer

It binds to deoxyhemoglobin, lowering oxygen affinity and promoting oxygen release in tissues.

Pulmonary System: Structure, Function, and Diseases

Guida di studio - Domande di pratica

Study guide - Flashcard