EXAM 3 – BIOS 252 / BIOS252:
ANATOMY AND PHYSIOLOGY II EXAM
QUESTIONS AND 100% VERIFIED ANSWERS
WITH RATIONALES GRADED A+ LATEST
CHAMBERLAIN UNIVERSITY
Question 1
Which structure of the heart is primarily responsible for preventing backflow of
blood into the left atrium during ventricular contraction?
A. Mitral valve
B. Tricuspid valve
C. Aortic semilunar valve
D. Pulmonary semilunar valve
Correct Answer: A
Rationale: The mitral (bicuspid) valve closes during ventricular systole to prevent
blood from flowing backward into the left atrium.
Question 2
A patient presents with narrowing of the coronary arteries due to lipid plaque
accumulation. This condition directly reduces blood flow to which structure?
A. Lungs
B. Myocardium
C. Brain
D. Kidneys
Correct Answer: B
Rationale: Coronary arteries supply oxygenated blood directly to the myocardium;
narrowing compromises cardiac muscle perfusion.
,Question 3
Which component of blood is primarily responsible for maintaining osmotic
pressure and fluid balance?
A. Erythrocytes
B. Leukocytes
C. Platelets
D. Plasma proteins
Correct Answer: D
Rationale: Plasma proteins, especially albumin, play a major role in maintaining
osmotic pressure and regulating fluid movement.
Question 4
Which leukocyte type is most involved in allergic reactions and parasitic
infections?
A. Neutrophils
B. Basophils
C. Eosinophils
D. Monocytes
Correct Answer: C
Rationale: Eosinophils are elevated in parasitic infections and allergic responses.
Question 5
The primary pacemaker of the heart is the:
A. Atrioventricular (AV) node
B. Purkinje fibers
C. Bundle branches
D. Sinoatrial (SA) node
,Correct Answer: D
Rationale: The SA node initiates electrical impulses that set the normal rhythm of
the heart.
Question 6
A decrease in blood pH due to increased carbon dioxide levels will stimulate which
structure to increase respiratory rate?
A. Medulla oblongata
B. Hypothalamus
C. Cerebellum
D. Pons
Correct Answer: A
Rationale: The medulla oblongata contains respiratory centers sensitive to changes
in CO₂ and pH.
Question 7
Which respiratory structure is the primary site of gas exchange?
A. Bronchi
B. Alveoli
C. Trachea
D. Bronchioles
Correct Answer: B
Rationale: Alveoli provide a thin, moist surface closely associated with capillaries
for efficient gas exchange.
, Question 8
A patient with emphysema most likely experiences impaired function of which
structure?
A. Diaphragm
B. Alveolar walls
C. Intercostal muscles
D. Pleural membranes
Correct Answer: B
Rationale: Emphysema damages alveolar walls, reducing surface area for gas
exchange.
Question 9
Which organ produces bile to aid in lipid digestion?
A. Pancreas
B. Gallbladder
C. Liver
D. Small intestine
Correct Answer: C
Rationale: The liver produces bile; the gallbladder stores and concentrates it.
Question 10
The majority of nutrient absorption occurs in which portion of the digestive tract?
A. Stomach
B. Duodenum
C. Jejunum
D. Ileum
Correct Answer: C
Rationale: The jejunum is the primary site for nutrient absorption due to its
extensive surface area.
ANATOMY AND PHYSIOLOGY II EXAM
QUESTIONS AND 100% VERIFIED ANSWERS
WITH RATIONALES GRADED A+ LATEST
CHAMBERLAIN UNIVERSITY
Question 1
Which structure of the heart is primarily responsible for preventing backflow of
blood into the left atrium during ventricular contraction?
A. Mitral valve
B. Tricuspid valve
C. Aortic semilunar valve
D. Pulmonary semilunar valve
Correct Answer: A
Rationale: The mitral (bicuspid) valve closes during ventricular systole to prevent
blood from flowing backward into the left atrium.
Question 2
A patient presents with narrowing of the coronary arteries due to lipid plaque
accumulation. This condition directly reduces blood flow to which structure?
A. Lungs
B. Myocardium
C. Brain
D. Kidneys
Correct Answer: B
Rationale: Coronary arteries supply oxygenated blood directly to the myocardium;
narrowing compromises cardiac muscle perfusion.
,Question 3
Which component of blood is primarily responsible for maintaining osmotic
pressure and fluid balance?
A. Erythrocytes
B. Leukocytes
C. Platelets
D. Plasma proteins
Correct Answer: D
Rationale: Plasma proteins, especially albumin, play a major role in maintaining
osmotic pressure and regulating fluid movement.
Question 4
Which leukocyte type is most involved in allergic reactions and parasitic
infections?
A. Neutrophils
B. Basophils
C. Eosinophils
D. Monocytes
Correct Answer: C
Rationale: Eosinophils are elevated in parasitic infections and allergic responses.
Question 5
The primary pacemaker of the heart is the:
A. Atrioventricular (AV) node
B. Purkinje fibers
C. Bundle branches
D. Sinoatrial (SA) node
,Correct Answer: D
Rationale: The SA node initiates electrical impulses that set the normal rhythm of
the heart.
Question 6
A decrease in blood pH due to increased carbon dioxide levels will stimulate which
structure to increase respiratory rate?
A. Medulla oblongata
B. Hypothalamus
C. Cerebellum
D. Pons
Correct Answer: A
Rationale: The medulla oblongata contains respiratory centers sensitive to changes
in CO₂ and pH.
Question 7
Which respiratory structure is the primary site of gas exchange?
A. Bronchi
B. Alveoli
C. Trachea
D. Bronchioles
Correct Answer: B
Rationale: Alveoli provide a thin, moist surface closely associated with capillaries
for efficient gas exchange.
, Question 8
A patient with emphysema most likely experiences impaired function of which
structure?
A. Diaphragm
B. Alveolar walls
C. Intercostal muscles
D. Pleural membranes
Correct Answer: B
Rationale: Emphysema damages alveolar walls, reducing surface area for gas
exchange.
Question 9
Which organ produces bile to aid in lipid digestion?
A. Pancreas
B. Gallbladder
C. Liver
D. Small intestine
Correct Answer: C
Rationale: The liver produces bile; the gallbladder stores and concentrates it.
Question 10
The majority of nutrient absorption occurs in which portion of the digestive tract?
A. Stomach
B. Duodenum
C. Jejunum
D. Ileum
Correct Answer: C
Rationale: The jejunum is the primary site for nutrient absorption due to its
extensive surface area.
