BIOS 256 Week 6 Quiz Exam 3 (Latest
Update ) Anatomy and
Physiology IV with Lab | Questions &
Answers | 100% Correct | Grade A –
Chamberlain
1. What is the primary function of the respiratory system?
A. Transport nutrients
B. Gas exchange
C. Hormone regulation
D. Waste excretion
Correct Answer: B
Rationale: The respiratory system allows oxygen to enter the body
and removes carbon dioxide.
2. Which structure serves as the main airway to the lungs?
A. Bronchioles
B. Trachea
C. Pharynx
D. Larynx
Correct Answer: B
Rationale: The trachea is the main passage that carries air to the
bronchi.
,3. Where does external respiration occur?
A. Alveoli
B. Tissue cells
C. Bronchi
D. Trachea
Correct Answer: A
Rationale: External respiration occurs between alveoli and
pulmonary capillaries.
4. Which muscle contracts to expand the thoracic cavity during
inhalation?
A. Diaphragm
B. Abdominals
C. Sternocleidomastoid
D. Pectoralis minor
Correct Answer: A
Rationale: The diaphragm contracts downward to increase lung
volume.
5. What is tidal volume?
A. Maximum air exhaled
B. Air inhaled or exhaled during normal breathing
C. Air left after exhalation
D. Air forced in after deep inhalation
Correct Answer: B
,Rationale: Tidal volume is the volume of air exchanged in a single
normal breath.
6. What is the role of surfactant in alveoli?
A. Increase mucus
B. Reduce surface tension
C. Enhance oxygen transport
D. Stimulate breathing
Correct Answer: B
Rationale: Surfactant prevents alveolar collapse by lowering surface
tension.
7. Which structure prevents food from entering the trachea?
A. Epiglottis
B. Larynx
C. Pharynx
D. Bronchi
Correct Answer: A
Rationale: The epiglottis covers the trachea during swallowing.
8. What is the main component of air by volume?
A. Oxygen
B. Carbon dioxide
C. Nitrogen
D. Hydrogen
, Correct Answer: C
Rationale: Nitrogen constitutes approximately 78% of atmospheric
air.
9. Which gas primarily regulates respiratory rate?
A. Oxygen
B. Carbon dioxide
C. Nitrogen
D. Hydrogen
Correct Answer: B
Rationale: High levels of CO₂ in the blood stimulate the respiratory
center.
10. Which blood vessels carry oxygenated blood from lungs to the
heart?
A. Pulmonary arteries
B. Pulmonary veins
C. Aorta
D. Vena cava
Correct Answer: B
Rationale: Pulmonary veins transport oxygen-rich blood to the left
atrium.
11. What is the role of alveoli?
Update ) Anatomy and
Physiology IV with Lab | Questions &
Answers | 100% Correct | Grade A –
Chamberlain
1. What is the primary function of the respiratory system?
A. Transport nutrients
B. Gas exchange
C. Hormone regulation
D. Waste excretion
Correct Answer: B
Rationale: The respiratory system allows oxygen to enter the body
and removes carbon dioxide.
2. Which structure serves as the main airway to the lungs?
A. Bronchioles
B. Trachea
C. Pharynx
D. Larynx
Correct Answer: B
Rationale: The trachea is the main passage that carries air to the
bronchi.
,3. Where does external respiration occur?
A. Alveoli
B. Tissue cells
C. Bronchi
D. Trachea
Correct Answer: A
Rationale: External respiration occurs between alveoli and
pulmonary capillaries.
4. Which muscle contracts to expand the thoracic cavity during
inhalation?
A. Diaphragm
B. Abdominals
C. Sternocleidomastoid
D. Pectoralis minor
Correct Answer: A
Rationale: The diaphragm contracts downward to increase lung
volume.
5. What is tidal volume?
A. Maximum air exhaled
B. Air inhaled or exhaled during normal breathing
C. Air left after exhalation
D. Air forced in after deep inhalation
Correct Answer: B
,Rationale: Tidal volume is the volume of air exchanged in a single
normal breath.
6. What is the role of surfactant in alveoli?
A. Increase mucus
B. Reduce surface tension
C. Enhance oxygen transport
D. Stimulate breathing
Correct Answer: B
Rationale: Surfactant prevents alveolar collapse by lowering surface
tension.
7. Which structure prevents food from entering the trachea?
A. Epiglottis
B. Larynx
C. Pharynx
D. Bronchi
Correct Answer: A
Rationale: The epiglottis covers the trachea during swallowing.
8. What is the main component of air by volume?
A. Oxygen
B. Carbon dioxide
C. Nitrogen
D. Hydrogen
, Correct Answer: C
Rationale: Nitrogen constitutes approximately 78% of atmospheric
air.
9. Which gas primarily regulates respiratory rate?
A. Oxygen
B. Carbon dioxide
C. Nitrogen
D. Hydrogen
Correct Answer: B
Rationale: High levels of CO₂ in the blood stimulate the respiratory
center.
10. Which blood vessels carry oxygenated blood from lungs to the
heart?
A. Pulmonary arteries
B. Pulmonary veins
C. Aorta
D. Vena cava
Correct Answer: B
Rationale: Pulmonary veins transport oxygen-rich blood to the left
atrium.
11. What is the role of alveoli?
