BIOL251 HUMAN ANATOMY &
PHYSIOLOGY EXAM 2026 ALL
QUESTIONS AND CORRECT DETAILED
ANSWERS WITH RATIONALES
ALREADY A GRADED | NEW AND
REVISED
1. A patient presents with muscle weakness due to impaired calcium
release from the sarcoplasmic reticulum. Which protein is directly
responsible for initiating calcium release during muscle
contraction?
A. Troponin
B. Ryanodine receptor
C. Tropomyosin
D. Myosin ATPase
The ryanodine receptor forms the calcium release channel in the
sarcoplasmic reticulum, enabling excitation–contraction
coupling.
,2. Which anatomical feature increases the efficiency of gas exchange
in the lungs?
A. Smooth muscle thickness
B. Large alveolar surface area
C. Presence of cartilage
D. High blood viscosity
Gas exchange efficiency depends on maximizing surface area
and minimizing diffusion distance, both achieved by alveoli.
3. A decrease in blood pH stimulates which immediate physiological
response?
A. Reduced respiratory rate
B. Increased ventilation
C. Decreased renal filtration
D. Suppressed chemoreceptor activity
Chemoreceptors detect low pH and stimulate increased
ventilation to remove CO₂.
4. Which structure connects muscle to bone?
A. Ligament
B. Tendon
C. Aponeurosis
D. Fascia
Tendons transmit force from muscle to bone.
, 5. During depolarization of a neuron, which ion primarily moves
across the membrane?
A. Potassium efflux
B. Sodium influx
C. Calcium efflux
D. Chloride influx
Sodium influx causes rapid depolarization during an action
potential.
6. A patient with damage to the hypothalamus would most likely
experience difficulty regulating:
A. Voluntary movement
B. Vision
C. Body temperature
D. Hearing
The hypothalamus is the primary thermoregulatory center.
7. Which blood vessel type has the thickest tunica media?
A. Veins
B. Capillaries
C. Arteries
D. Venules
Arteries require thick smooth muscle layers to withstand high
pressure.
PHYSIOLOGY EXAM 2026 ALL
QUESTIONS AND CORRECT DETAILED
ANSWERS WITH RATIONALES
ALREADY A GRADED | NEW AND
REVISED
1. A patient presents with muscle weakness due to impaired calcium
release from the sarcoplasmic reticulum. Which protein is directly
responsible for initiating calcium release during muscle
contraction?
A. Troponin
B. Ryanodine receptor
C. Tropomyosin
D. Myosin ATPase
The ryanodine receptor forms the calcium release channel in the
sarcoplasmic reticulum, enabling excitation–contraction
coupling.
,2. Which anatomical feature increases the efficiency of gas exchange
in the lungs?
A. Smooth muscle thickness
B. Large alveolar surface area
C. Presence of cartilage
D. High blood viscosity
Gas exchange efficiency depends on maximizing surface area
and minimizing diffusion distance, both achieved by alveoli.
3. A decrease in blood pH stimulates which immediate physiological
response?
A. Reduced respiratory rate
B. Increased ventilation
C. Decreased renal filtration
D. Suppressed chemoreceptor activity
Chemoreceptors detect low pH and stimulate increased
ventilation to remove CO₂.
4. Which structure connects muscle to bone?
A. Ligament
B. Tendon
C. Aponeurosis
D. Fascia
Tendons transmit force from muscle to bone.
, 5. During depolarization of a neuron, which ion primarily moves
across the membrane?
A. Potassium efflux
B. Sodium influx
C. Calcium efflux
D. Chloride influx
Sodium influx causes rapid depolarization during an action
potential.
6. A patient with damage to the hypothalamus would most likely
experience difficulty regulating:
A. Voluntary movement
B. Vision
C. Body temperature
D. Hearing
The hypothalamus is the primary thermoregulatory center.
7. Which blood vessel type has the thickest tunica media?
A. Veins
B. Capillaries
C. Arteries
D. Venules
Arteries require thick smooth muscle layers to withstand high
pressure.
