BIOS252 / BIOS 252 FINAL EXAM (LATEST 2026) : ANATOMY AND
PHYSIOLOGY II CHAMBERLAIN,160 CORRECT QUESTIONS AND
ANSWERS, ALREADY GRADED A+
1
Which structure of the heart is responsible for initiating the electrical impulses that
set the pace for the cardiac cycle?
A) Atrioventricular (AV) node
B) Purkinje fibers
C) Sinoatrial (SA) node
D) Bundle of His
Correct Answer: C) Sinoatrial (SA) node
Explanation: The SA node, located in the right atrium near the superior vena cava,
is known as the heart’s natural pacemaker. It generates spontaneous action
potentials due to automaticity, setting the rhythm of approximately 60–100 beats
per minute in a healthy adult. These impulses spread through the atria, causing
atrial contraction, before reaching the AV node. Dysfunction of the SA node may
require artificial pacemaker placement. The AV node and Purkinje fibers serve
important conduction roles but are not the primary pacemaker under normal
physiology.
2
Which blood vessel carries oxygen-rich blood from the lungs to the left atrium of
the heart?
A) Pulmonary veins
B) Pulmonary arteries
C) Superior vena cava
D) Coronary sinus
,Correct Answer: A) Pulmonary veins
Explanation: Unlike most veins, which carry deoxygenated blood, the pulmonary
veins are unique because they transport oxygenated blood from the lungs to the left
atrium. There are typically four pulmonary veins, two from each lung. From the
left atrium, blood moves into the left ventricle and is pumped through the aorta to
supply systemic circulation. In contrast, the pulmonary arteries carry
deoxygenated blood from the right ventricle to the lungs for gas exchange.
3
Which organelle within the cell is primarily responsible for producing ATP through
aerobic respiration?
A) Ribosome
B) Mitochondrion
C) Endoplasmic reticulum
D) Golgi apparatus
Correct Answer: B) Mitochondrion
Explanation: The mitochondrion is often called the “powerhouse of the cell”
because it generates ATP via oxidative phosphorylation in the electron transport
chain. It requires oxygen and substrates such as glucose and fatty acids. The inner
mitochondrial membrane contains cristae, which increase surface area for ATP
production. While ribosomes synthesize proteins, the endoplasmic reticulum
processes and transports molecules, and the Golgi apparatus modifies and
packages proteins. Only mitochondria directly generate the majority of cellular
ATP, which is essential for muscle contraction, nerve conduction, and all energy-
dependent processes in the body.
4
In respiratory physiology experiments, tidal volume is measured. Which statement
best describes tidal volume during quiet breathing in a healthy adult?
,A) The maximum volume that can be exhaled after a normal breath
B) The amount of air inspired or expired with each normal breath
C) The volume of air remaining in lungs after maximal exhalation
D) The total volume lungs can hold after maximal inspiration
Correct Answer: B) The amount of air inspired or expired with each normal
breath
Explanation: Tidal volume averages 500 mL in adults and represents the baseline
breathing cycle without effort.
5
During digestion lab activities, a student learns that bile plays a critical role in fat
metabolism. Which of the following best describes the primary function of bile in
the small intestine?
A) Provides digestive enzymes to hydrolyze proteins
B) Neutralizes acidic chyme to protect intestinal lining
C) Emulsifies lipids to increase surface area for enzymatic action
D) Absorbs fatty acids directly into lymphatic circulation
Correct Answer: C) Emulsifies lipids to increase surface area for enzymatic
action
Explanation: Bile salts emulsify fats, making them more accessible for lipase
digestion and absorption in the small intestine.
6
A student in lab is measuring lung capacities using a spirometer. Which of the
following represents the maximum amount of air that can be exhaled after a normal
tidal expiration?
A) Vital capacity
B) Residual volume
C) Expiratory reserve volume
D) Inspiratory reserve volume
, Correct Answer: C) Expiratory reserve volume
Explanation: ERV is the additional air exhaled beyond tidal expiration. Vital
capacity is the sum of IRV + TV + ERV.
7
A patient is experiencing shortness of breath due to fluid accumulation in the
alveoli. This condition directly interferes with which key physiological process in
pulmonary gas exchange?
A) Perfusion of pulmonary capillaries
B) Oxygen diffusion across the respiratory membrane
C) Transport of carbon dioxide in plasma
D) Neural control of respiratory rhythm
Correct Answer: B) Oxygen diffusion across the respiratory membrane
Explanation: Alveolar flooding increases diffusion distance, impairing oxygen
transfer and leading to hypoxemia.
8
Which layer of the gastrointestinal tract is primarily responsible for peristaltic
contractions that move food through the digestive system?
A) Serosa
B) Mucosa
C) Submucosa
D) Muscularis externa
Correct Answer: D) Muscularis externa
Explanation: Smooth muscle layers of the muscularis externa (circular and
longitudinal) generate peristalsis and segmentation.
9
In a renal physiology experiment, a student identifies the portion of the nephron
where the majority of sodium, glucose, and amino acids are reabsorbed. Which
structure is this?
PHYSIOLOGY II CHAMBERLAIN,160 CORRECT QUESTIONS AND
ANSWERS, ALREADY GRADED A+
1
Which structure of the heart is responsible for initiating the electrical impulses that
set the pace for the cardiac cycle?
A) Atrioventricular (AV) node
B) Purkinje fibers
C) Sinoatrial (SA) node
D) Bundle of His
Correct Answer: C) Sinoatrial (SA) node
Explanation: The SA node, located in the right atrium near the superior vena cava,
is known as the heart’s natural pacemaker. It generates spontaneous action
potentials due to automaticity, setting the rhythm of approximately 60–100 beats
per minute in a healthy adult. These impulses spread through the atria, causing
atrial contraction, before reaching the AV node. Dysfunction of the SA node may
require artificial pacemaker placement. The AV node and Purkinje fibers serve
important conduction roles but are not the primary pacemaker under normal
physiology.
2
Which blood vessel carries oxygen-rich blood from the lungs to the left atrium of
the heart?
A) Pulmonary veins
B) Pulmonary arteries
C) Superior vena cava
D) Coronary sinus
,Correct Answer: A) Pulmonary veins
Explanation: Unlike most veins, which carry deoxygenated blood, the pulmonary
veins are unique because they transport oxygenated blood from the lungs to the left
atrium. There are typically four pulmonary veins, two from each lung. From the
left atrium, blood moves into the left ventricle and is pumped through the aorta to
supply systemic circulation. In contrast, the pulmonary arteries carry
deoxygenated blood from the right ventricle to the lungs for gas exchange.
3
Which organelle within the cell is primarily responsible for producing ATP through
aerobic respiration?
A) Ribosome
B) Mitochondrion
C) Endoplasmic reticulum
D) Golgi apparatus
Correct Answer: B) Mitochondrion
Explanation: The mitochondrion is often called the “powerhouse of the cell”
because it generates ATP via oxidative phosphorylation in the electron transport
chain. It requires oxygen and substrates such as glucose and fatty acids. The inner
mitochondrial membrane contains cristae, which increase surface area for ATP
production. While ribosomes synthesize proteins, the endoplasmic reticulum
processes and transports molecules, and the Golgi apparatus modifies and
packages proteins. Only mitochondria directly generate the majority of cellular
ATP, which is essential for muscle contraction, nerve conduction, and all energy-
dependent processes in the body.
4
In respiratory physiology experiments, tidal volume is measured. Which statement
best describes tidal volume during quiet breathing in a healthy adult?
,A) The maximum volume that can be exhaled after a normal breath
B) The amount of air inspired or expired with each normal breath
C) The volume of air remaining in lungs after maximal exhalation
D) The total volume lungs can hold after maximal inspiration
Correct Answer: B) The amount of air inspired or expired with each normal
breath
Explanation: Tidal volume averages 500 mL in adults and represents the baseline
breathing cycle without effort.
5
During digestion lab activities, a student learns that bile plays a critical role in fat
metabolism. Which of the following best describes the primary function of bile in
the small intestine?
A) Provides digestive enzymes to hydrolyze proteins
B) Neutralizes acidic chyme to protect intestinal lining
C) Emulsifies lipids to increase surface area for enzymatic action
D) Absorbs fatty acids directly into lymphatic circulation
Correct Answer: C) Emulsifies lipids to increase surface area for enzymatic
action
Explanation: Bile salts emulsify fats, making them more accessible for lipase
digestion and absorption in the small intestine.
6
A student in lab is measuring lung capacities using a spirometer. Which of the
following represents the maximum amount of air that can be exhaled after a normal
tidal expiration?
A) Vital capacity
B) Residual volume
C) Expiratory reserve volume
D) Inspiratory reserve volume
, Correct Answer: C) Expiratory reserve volume
Explanation: ERV is the additional air exhaled beyond tidal expiration. Vital
capacity is the sum of IRV + TV + ERV.
7
A patient is experiencing shortness of breath due to fluid accumulation in the
alveoli. This condition directly interferes with which key physiological process in
pulmonary gas exchange?
A) Perfusion of pulmonary capillaries
B) Oxygen diffusion across the respiratory membrane
C) Transport of carbon dioxide in plasma
D) Neural control of respiratory rhythm
Correct Answer: B) Oxygen diffusion across the respiratory membrane
Explanation: Alveolar flooding increases diffusion distance, impairing oxygen
transfer and leading to hypoxemia.
8
Which layer of the gastrointestinal tract is primarily responsible for peristaltic
contractions that move food through the digestive system?
A) Serosa
B) Mucosa
C) Submucosa
D) Muscularis externa
Correct Answer: D) Muscularis externa
Explanation: Smooth muscle layers of the muscularis externa (circular and
longitudinal) generate peristalsis and segmentation.
9
In a renal physiology experiment, a student identifies the portion of the nephron
where the majority of sodium, glucose, and amino acids are reabsorbed. Which
structure is this?
