BMS 300 EXAM 4 [2026/2027] UPDATED ACTUAL Exam
Questions and Answers | Frequently Tested Questions
200 Questions with Verified Answers & Detailed Explanations
FORMATTING LEGEND:
• Bold Italic = Correct Answer
• Italic = Rationale/Explanation
TABLE OF CONTENTS
Section Questions
Respiratory System 1-55
Renal System 56-105
Digestive System 106-155
Cardiovascular & Blood 156-175
Endocrine & Reproductive 176-200
,SECTION 1: RESPIRATORY SYSTEM (Questions 1-55)
QUESTION 1
Gas exchange occurs in which structure of the respiratory system?
A) Bronchioles
B) Alveolar sacs
C) Trachea
D) Terminal bronchioles
CORRECT ANSWER: B) Alveolar sacs
Rationale: Gas exchange (oxygen and carbon dioxide diffusion) occurs across the thin walls
of the alveoli and alveolar sacs, where the respiratory membrane is only two cells
thick. The trachea, bronchi, and bronchioles are part of the conducting zone and do not
participate in gas exchange.
QUESTION 2
The pleural sac must have what type of pressure?
A) Positive pressure
B) Negative pressure
C) Atmospheric pressure
D) Zero pressure
CORRECT ANSWER: B) Negative pressure
Rationale: The intrapleural pressure is negative (subatmospheric) relative to atmospheric
pressure. This negative pressure keeps the lungs expanded and prevents them from
,collapsing. It is created by the elastic recoil of the lungs and the surface tension of the
pleural fluid.
QUESTION 3
What is the function of Type I pneumocytes?
A) Produce surfactant
B) Responsible for gas exchange
C) Defend against pathogens
D) Secrete mucus
CORRECT ANSWER: B) Responsible for gas exchange
Rationale: Type I pneumocytes are thin, squamous epithelial cells that line the alveoli and
are responsible for gas exchange. Type II pneumocytes produce surfactant.
QUESTION 4
What is the function of surfactant produced by Type II pneumocytes?
A) Increases surface tension
B) Decreases surface tension and increases lung compliance
C) Promotes gas exchange
D) Traps pathogens
CORRECT ANSWER: B) Decreases surface tension and increases lung compliance
Rationale: Surfactant is a detergent-like substance that decreases surface tension in the
alveoli, preventing collapse and increasing lung compliance. This makes breathing easier
and prevents atelectasis.
, QUESTION 5
Epithelial cells of the alveoli are covered by a layer of water that does what to surface
tension?
A) Decreases surface tension
B) Increases surface tension
C) Has no effect on surface tension
D) Neutralizes surface tension
CORRECT ANSWER: B) Increases surface tension
Rationale: The layer of water covering alveolar epithelial cells creates surface tension that
tends to collapse the alveoli. Surfactant is needed to reduce this surface tension.
QUESTION 6
Damage to lower motor neurons of C3, C4, and C5 (phrenic nerve) has what effect?
A) Paralysis of the intercostal muscles
B) Paralysis of the diaphragm
C) Increased respiratory rate
D) No effect on breathing
CORRECT ANSWER: B) Paralysis of the diaphragm
Rationale: The phrenic nerve (C3-C5) innervates the diaphragm. Damage to these spinal
segments results in diaphragm paralysis, which can be life-threatening as the diaphragm
is the primary muscle of inspiration.
Questions and Answers | Frequently Tested Questions
200 Questions with Verified Answers & Detailed Explanations
FORMATTING LEGEND:
• Bold Italic = Correct Answer
• Italic = Rationale/Explanation
TABLE OF CONTENTS
Section Questions
Respiratory System 1-55
Renal System 56-105
Digestive System 106-155
Cardiovascular & Blood 156-175
Endocrine & Reproductive 176-200
,SECTION 1: RESPIRATORY SYSTEM (Questions 1-55)
QUESTION 1
Gas exchange occurs in which structure of the respiratory system?
A) Bronchioles
B) Alveolar sacs
C) Trachea
D) Terminal bronchioles
CORRECT ANSWER: B) Alveolar sacs
Rationale: Gas exchange (oxygen and carbon dioxide diffusion) occurs across the thin walls
of the alveoli and alveolar sacs, where the respiratory membrane is only two cells
thick. The trachea, bronchi, and bronchioles are part of the conducting zone and do not
participate in gas exchange.
QUESTION 2
The pleural sac must have what type of pressure?
A) Positive pressure
B) Negative pressure
C) Atmospheric pressure
D) Zero pressure
CORRECT ANSWER: B) Negative pressure
Rationale: The intrapleural pressure is negative (subatmospheric) relative to atmospheric
pressure. This negative pressure keeps the lungs expanded and prevents them from
,collapsing. It is created by the elastic recoil of the lungs and the surface tension of the
pleural fluid.
QUESTION 3
What is the function of Type I pneumocytes?
A) Produce surfactant
B) Responsible for gas exchange
C) Defend against pathogens
D) Secrete mucus
CORRECT ANSWER: B) Responsible for gas exchange
Rationale: Type I pneumocytes are thin, squamous epithelial cells that line the alveoli and
are responsible for gas exchange. Type II pneumocytes produce surfactant.
QUESTION 4
What is the function of surfactant produced by Type II pneumocytes?
A) Increases surface tension
B) Decreases surface tension and increases lung compliance
C) Promotes gas exchange
D) Traps pathogens
CORRECT ANSWER: B) Decreases surface tension and increases lung compliance
Rationale: Surfactant is a detergent-like substance that decreases surface tension in the
alveoli, preventing collapse and increasing lung compliance. This makes breathing easier
and prevents atelectasis.
, QUESTION 5
Epithelial cells of the alveoli are covered by a layer of water that does what to surface
tension?
A) Decreases surface tension
B) Increases surface tension
C) Has no effect on surface tension
D) Neutralizes surface tension
CORRECT ANSWER: B) Increases surface tension
Rationale: The layer of water covering alveolar epithelial cells creates surface tension that
tends to collapse the alveoli. Surfactant is needed to reduce this surface tension.
QUESTION 6
Damage to lower motor neurons of C3, C4, and C5 (phrenic nerve) has what effect?
A) Paralysis of the intercostal muscles
B) Paralysis of the diaphragm
C) Increased respiratory rate
D) No effect on breathing
CORRECT ANSWER: B) Paralysis of the diaphragm
Rationale: The phrenic nerve (C3-C5) innervates the diaphragm. Damage to these spinal
segments results in diaphragm paralysis, which can be life-threatening as the diaphragm
is the primary muscle of inspiration.
