WorksheetsRespiratory System Quiz
Total questions: 21
Worksheet time: 12mins
What is internal respiration?
Exchange of gases in lungs
Breathing air in
Use of oxygen by cells
Transport of blood
What does external respiration involve?
Gas exchange between lungs and blood
Production of ATP
Use of O2 by the cells
Movement of muscles
What is the main function of the conducting zone?
Gas exchange
Transport of air
Production of mucus
Regulation of blood pressure
Which cells in the alveoli are primarily responsible for secreting surfactant?
Type I alveolar cells
Type II alveolar cells
Alveolar macrophages
Endothelial cells
What is the pressure in the alveoli during expiration?
-1 mmHg
+1 mmHg
760 mmHg
0 mmHg
The normal resting respiratory rate is
5-10 cycles / minute
30-35 cycles / minute
12-16 cycles / minute
20-25 cycles / minute
Concerning the intrapleural (intrathoracic pressure), which is correct ?
The pressure inside the lung alveoli
The lungs tend to expand outward, while the thoracic wall tends to recoil inward
Its negativity helps venous and lymphatic return
it becomes highly positive in Muller's experiment
A healthy, 45-year-old man is reading the newspaper. Which of the following muscles are used for quiet breathing?
Diaphragm
Internal intercostals muscles
Abdominal muscles
sternomastoid muscle
A healthy, 25-year-old student participates in a 10-km charity run Which of the following muscles does the student use (contract) during forced expiration?
Scaleni
Diaphragm and external intercostal muscles
Internal intercostals and abdominal muscles
Diaphragm only
The normal resting tidal volume in a healthy adult is approximately
150 mL
300 mL
500 mL
800 mL
During normal inspiration, the intra-alveolar pressure becomes approximately
+1 mmHg
0 mmHg
–1 mmHg
–6 mmHg
Hypoxic hypoxia is characterized by which of the following?
Low tissue utilization of oxygen
Reduced PO₂ of arterial blood
Reduced hemoglobin concentration
Low blood flow to tissues
A premature newborn presents with severe difficulty breathing shortly after birth. The lungs show repeated alveolar collapse. Which physiological defect best explains this condition?
Decreased alveolar macrophage activity
Absence of type I alveolar cells
Insufficient surfactant secretion
Excessive bronchoconstriction
During deep inspiration, the intrapleural pressure becomes more negative. The primary reason for this change is
Increased surface tension in alveoli
Relaxation of inspiratory muscles
Increased recoil tendency of the lungs
Decrease in thoracic volume
Which of the following will increase vital capacity?
Pregnancy
Old age
Left-sided heart failure
Athletic training
A patient breathes 500 mL of air per breath. If anatomical dead space is 150 mL, the volume of air that undergoes gas exchange equals
300 mL
200 mL
350 mL
250 mL
Which factor most directly decreases diffusion across the respiratory membrane?
Increased alveolar surface area
Decreased membrane thickness
Increased pressure gradient
Accumulation of fluid in interstitial space
A patient has an alveolar pressure of 0 mmHg at end-expiration and an intrapleural pressure of –4 mmHg. The trans-pulmonary pressure at this point is
–4 mmHg
0 mmHg
+4 mmHg
+8 mmHg
In a healthy adult, physiological dead space equals anatomical dead space primarily because
Alveoli have high surface tension
All alveoli have adequate blood flow
Bronchioles lack smooth muscle
Gas exchange occurs in large bronchi
Cyanosis is bluish coloration of skin & mucous membranes due to
presence of less than 5 gm reduced HB/100 ml capillary blood
reduced surfactant levels
low arterial PO₂
presence of 5 gm reduced HB/100 ml capillary blood
A patient with severe anemia has normal arterial PO₂ but shows signs of tissue oxygen deficiency. This represents which type of hypoxia?
Hypoxic hypoxia
Anemic hypoxia
Histotoxic hypoxia
Stagnant hypoxia
