Mader's Understanding Human Anatomy &
Physiology 10th Edition Advanced Prep: Master
Chapters 1-19 Practice Questions & Detailed
Explanations
Subject: Comprehensive Human Anatomy & Physiology (Chapters 1-19)
Question 1: A research team is investigating a novel endocrine disruptor that specifically targets
the second messenger system in cells responding to non-steroid hormones. If this chemical
inhibits the activation of adenylate cyclase, which of the following downstream events would be
most immediately impacted in a target cell?
A) The transport of the hormone-receptor complex into the nucleus
B) The conversion of ATP into cyclic AMP (cAMP)
C) The direct phosphorylation of intracellular transcription factors
D) The binding of the hormone to the plasma membrane receptor
Correct Answer: B) The conversion of ATP into cyclic AMP (cAMP)
Explanation: Non-steroid hormones (like peptide hormones) typically utilize a second messenger
system because they cannot cross the plasma membrane. They bind to receptors on the cell
surface, which activates G-proteins, subsequently activating adenylate cyclase. Adenylate
cyclase is the enzyme responsible for catalyzing the conversion of ATP to cAMP. Inhibiting this
enzyme prevents the production of the second messenger, effectively blocking the signaling
cascade before it can initiate protein kinase activity.
Question 2: During a histological examination of a patient’s tissue sample, you observe cells that
contain an abundance of both rough endoplasmic reticulum and Golgi apparatus, with numerous
secretory vesicles oriented toward the apical surface. Which tissue type are you most likely
observing?
A) Simple squamous epithelium specialized for filtration
B) Dense regular connective tissue specialized for tensile strength
C) Glandular epithelium specialized for protein secretion
D) Reticular connective tissue specialized for structural support
Correct Answer: C) Glandular epithelium specialized for protein secretion
,Explanation: The presence of extensive rough endoplasmic reticulum (for protein synthesis) and
a prominent Golgi apparatus (for processing and packaging) is characteristic of cells actively
secreting proteins. Secretory vesicles at the apical surface confirm an exocrine or endocrine
glandular function. Simple squamous cells are thin and lack such metabolic machinery; dense
regular connective tissue is dominated by collagen fibers; reticular tissue is dominated by
reticular fibers and immune cells.
Question 3: A patient presents with a severe electrolyte imbalance characterized by
hyperkalemia. Which physiological feedback loop is primarily responsible for the subsequent
secretion of aldosterone to mitigate this condition?
A) The hypothalamus-hypophyseal portal system
B) The renin-angiotensin-aldosterone system (RAAS)
C) The sympathetic nervous system's direct stimulation of the adrenal medulla
D) The negative feedback of high plasma potassium on the posterior pituitary
Correct Answer: B) The renin-angiotensin-aldosterone system (RAAS)
Explanation: While high potassium levels can directly stimulate the adrenal cortex to release
aldosterone, the RAAS is the broader homeostatic mechanism involved in systemic fluid and
electrolyte regulation. Aldosterone acts on the distal convoluted tubules and collecting ducts of
the nephron to promote potassium excretion and sodium reabsorption. The other options either
involve different hormones (like ADH) or different target tissues.
Question 4: In the context of bone remodeling, which cell type would be most active in a region
of the diaphysis experiencing high mechanical stress, and what is its primary chemical
mechanism of action?
A) Osteoclasts; secretion of calcium phosphate crystals
B) Osteoblasts; secretion of osteoid and subsequent mineralization
C) Osteocytes; sensing stress and inhibiting osteoclast activity
D) Chondroblasts; secretion of hyaline matrix
Correct Answer: B) Osteoblasts; secretion of osteoid and subsequent mineralization
Explanation: Wolff’s Law dictates that bone adapts to the loads under which it is placed.
Osteoblasts are the bone-forming cells responsible for secreting the organic matrix (osteoid) and
facilitating its mineralization, thereby increasing bone density in high-stress areas. Osteoclasts
are responsible for bone resorption (breaking down bone). While osteocytes sense stress, they do
not primarily build bone tissue.
,Question 5: If a patient is diagnosed with an autoimmune disease that selectively destroys the
myelin sheath of the central nervous system, which glial cell population is primarily affected?
A) Schwann cells
B) Satellite cells
C) Oligodendrocytes
D) Astrocytes
Correct Answer: C) Oligodendrocytes
Explanation: Myelin sheaths in the central nervous system (CNS) are produced and maintained
by oligodendrocytes. Schwann cells perform the same function, but only in the peripheral
nervous system (PNS). Astrocytes provide structural support and blood-brain barrier
maintenance, while satellite cells support neurons in the PNS ganglia.
Question 6: During a cardiac cycle, the "isovolumetric contraction" phase is defined by which of
the following hemodynamic states?
A) All four heart valves are closed; ventricular pressure rises rapidly.
B) Atrioventricular valves are open; aortic valve is closed.
C) Semilunar valves are open; atria are contracting.
D) All four heart valves are open; ventricular volume is constant.
Correct Answer: A) All four heart valves are closed; ventricular pressure rises rapidly.
Explanation: During isovolumetric contraction, the ventricles begin to contract. As ventricular
pressure exceeds atrial pressure, the AV valves snap shut (the first heart sound). Because the
pressure in the aorta/pulmonary trunk is still higher than in the ventricles, the semilunar valves
remain closed. Thus, the volume of blood in the ventricles remains constant while the pressure
increases.
Question 7: A patient suffers a spinal cord injury at the level of T6. Which of the following
respiratory muscles would be most significantly impaired, and what is the likely impact on total
lung capacity?
A) Diaphragm; severe reduction due to loss of phrenic nerve innervation
B) External intercostals; reduction in vital capacity due to restricted thoracic expansion
C) Sternocleidomastoid; minimal impact as it is an accessory muscle
, D) Internal intercostals; no impact on resting tidal volume
Correct Answer: B) External intercostals; reduction in vital capacity due to restricted
thoracic expansion
Explanation: The phrenic nerve originates from C3-C5, so a T6 injury spares the diaphragm,
which is the primary muscle of respiration. However, the external intercostal muscles are
innervated by thoracic spinal nerves (T1-T11). A T6 injury paralyzes the intercostals below that
level, reducing the ability to expand the thoracic cavity fully, thereby decreasing vital capacity
even if the diaphragm remains functional.
Question 8: In the nephron, where does the majority of obligatory water reabsorption occur, and
what is the driving force?
A) Collecting duct; ADH concentration gradient
B) Proximal convoluted tubule; osmotic gradient following active sodium transport
C) Distal convoluted tubule; aldosterone-regulated sodium transport
D) Loop of Henle; countercurrent multiplication
Correct Answer: B) Proximal convoluted tubule; osmotic gradient following active sodium
transport
Explanation: Obligatory water reabsorption refers to the passive movement of water that follows
solute reabsorption, primarily sodium. This occurs in the proximal convoluted tubule and the
descending limb of the loop of Henle. The active transport of sodium out of the tubule into the
interstitial space creates an osmotic gradient that pulls water through aquaporins.
Question 9: Which of the following best describes the structural and functional relationship
between the sarcolemma and the sarcoplasmic reticulum (SR) in skeletal muscle excitation-
contraction coupling?
A) The SR releases acetylcholine to trigger the sarcolemma.
B) The sarcolemma forms T-tubules that extend deep into the fiber to bring depolarization to the
SR.
C) The SR is continuous with the sarcolemma to allow ion flow.
D) The sarcolemma stores calcium, which is released upon SR depolarization.
Correct Answer: B) The sarcolemma forms T-tubules that extend deep into the fiber to
bring depolarization to the SR.
Physiology 10th Edition Advanced Prep: Master
Chapters 1-19 Practice Questions & Detailed
Explanations
Subject: Comprehensive Human Anatomy & Physiology (Chapters 1-19)
Question 1: A research team is investigating a novel endocrine disruptor that specifically targets
the second messenger system in cells responding to non-steroid hormones. If this chemical
inhibits the activation of adenylate cyclase, which of the following downstream events would be
most immediately impacted in a target cell?
A) The transport of the hormone-receptor complex into the nucleus
B) The conversion of ATP into cyclic AMP (cAMP)
C) The direct phosphorylation of intracellular transcription factors
D) The binding of the hormone to the plasma membrane receptor
Correct Answer: B) The conversion of ATP into cyclic AMP (cAMP)
Explanation: Non-steroid hormones (like peptide hormones) typically utilize a second messenger
system because they cannot cross the plasma membrane. They bind to receptors on the cell
surface, which activates G-proteins, subsequently activating adenylate cyclase. Adenylate
cyclase is the enzyme responsible for catalyzing the conversion of ATP to cAMP. Inhibiting this
enzyme prevents the production of the second messenger, effectively blocking the signaling
cascade before it can initiate protein kinase activity.
Question 2: During a histological examination of a patient’s tissue sample, you observe cells that
contain an abundance of both rough endoplasmic reticulum and Golgi apparatus, with numerous
secretory vesicles oriented toward the apical surface. Which tissue type are you most likely
observing?
A) Simple squamous epithelium specialized for filtration
B) Dense regular connective tissue specialized for tensile strength
C) Glandular epithelium specialized for protein secretion
D) Reticular connective tissue specialized for structural support
Correct Answer: C) Glandular epithelium specialized for protein secretion
,Explanation: The presence of extensive rough endoplasmic reticulum (for protein synthesis) and
a prominent Golgi apparatus (for processing and packaging) is characteristic of cells actively
secreting proteins. Secretory vesicles at the apical surface confirm an exocrine or endocrine
glandular function. Simple squamous cells are thin and lack such metabolic machinery; dense
regular connective tissue is dominated by collagen fibers; reticular tissue is dominated by
reticular fibers and immune cells.
Question 3: A patient presents with a severe electrolyte imbalance characterized by
hyperkalemia. Which physiological feedback loop is primarily responsible for the subsequent
secretion of aldosterone to mitigate this condition?
A) The hypothalamus-hypophyseal portal system
B) The renin-angiotensin-aldosterone system (RAAS)
C) The sympathetic nervous system's direct stimulation of the adrenal medulla
D) The negative feedback of high plasma potassium on the posterior pituitary
Correct Answer: B) The renin-angiotensin-aldosterone system (RAAS)
Explanation: While high potassium levels can directly stimulate the adrenal cortex to release
aldosterone, the RAAS is the broader homeostatic mechanism involved in systemic fluid and
electrolyte regulation. Aldosterone acts on the distal convoluted tubules and collecting ducts of
the nephron to promote potassium excretion and sodium reabsorption. The other options either
involve different hormones (like ADH) or different target tissues.
Question 4: In the context of bone remodeling, which cell type would be most active in a region
of the diaphysis experiencing high mechanical stress, and what is its primary chemical
mechanism of action?
A) Osteoclasts; secretion of calcium phosphate crystals
B) Osteoblasts; secretion of osteoid and subsequent mineralization
C) Osteocytes; sensing stress and inhibiting osteoclast activity
D) Chondroblasts; secretion of hyaline matrix
Correct Answer: B) Osteoblasts; secretion of osteoid and subsequent mineralization
Explanation: Wolff’s Law dictates that bone adapts to the loads under which it is placed.
Osteoblasts are the bone-forming cells responsible for secreting the organic matrix (osteoid) and
facilitating its mineralization, thereby increasing bone density in high-stress areas. Osteoclasts
are responsible for bone resorption (breaking down bone). While osteocytes sense stress, they do
not primarily build bone tissue.
,Question 5: If a patient is diagnosed with an autoimmune disease that selectively destroys the
myelin sheath of the central nervous system, which glial cell population is primarily affected?
A) Schwann cells
B) Satellite cells
C) Oligodendrocytes
D) Astrocytes
Correct Answer: C) Oligodendrocytes
Explanation: Myelin sheaths in the central nervous system (CNS) are produced and maintained
by oligodendrocytes. Schwann cells perform the same function, but only in the peripheral
nervous system (PNS). Astrocytes provide structural support and blood-brain barrier
maintenance, while satellite cells support neurons in the PNS ganglia.
Question 6: During a cardiac cycle, the "isovolumetric contraction" phase is defined by which of
the following hemodynamic states?
A) All four heart valves are closed; ventricular pressure rises rapidly.
B) Atrioventricular valves are open; aortic valve is closed.
C) Semilunar valves are open; atria are contracting.
D) All four heart valves are open; ventricular volume is constant.
Correct Answer: A) All four heart valves are closed; ventricular pressure rises rapidly.
Explanation: During isovolumetric contraction, the ventricles begin to contract. As ventricular
pressure exceeds atrial pressure, the AV valves snap shut (the first heart sound). Because the
pressure in the aorta/pulmonary trunk is still higher than in the ventricles, the semilunar valves
remain closed. Thus, the volume of blood in the ventricles remains constant while the pressure
increases.
Question 7: A patient suffers a spinal cord injury at the level of T6. Which of the following
respiratory muscles would be most significantly impaired, and what is the likely impact on total
lung capacity?
A) Diaphragm; severe reduction due to loss of phrenic nerve innervation
B) External intercostals; reduction in vital capacity due to restricted thoracic expansion
C) Sternocleidomastoid; minimal impact as it is an accessory muscle
, D) Internal intercostals; no impact on resting tidal volume
Correct Answer: B) External intercostals; reduction in vital capacity due to restricted
thoracic expansion
Explanation: The phrenic nerve originates from C3-C5, so a T6 injury spares the diaphragm,
which is the primary muscle of respiration. However, the external intercostal muscles are
innervated by thoracic spinal nerves (T1-T11). A T6 injury paralyzes the intercostals below that
level, reducing the ability to expand the thoracic cavity fully, thereby decreasing vital capacity
even if the diaphragm remains functional.
Question 8: In the nephron, where does the majority of obligatory water reabsorption occur, and
what is the driving force?
A) Collecting duct; ADH concentration gradient
B) Proximal convoluted tubule; osmotic gradient following active sodium transport
C) Distal convoluted tubule; aldosterone-regulated sodium transport
D) Loop of Henle; countercurrent multiplication
Correct Answer: B) Proximal convoluted tubule; osmotic gradient following active sodium
transport
Explanation: Obligatory water reabsorption refers to the passive movement of water that follows
solute reabsorption, primarily sodium. This occurs in the proximal convoluted tubule and the
descending limb of the loop of Henle. The active transport of sodium out of the tubule into the
interstitial space creates an osmotic gradient that pulls water through aquaporins.
Question 9: Which of the following best describes the structural and functional relationship
between the sarcolemma and the sarcoplasmic reticulum (SR) in skeletal muscle excitation-
contraction coupling?
A) The SR releases acetylcholine to trigger the sarcolemma.
B) The sarcolemma forms T-tubules that extend deep into the fiber to bring depolarization to the
SR.
C) The SR is continuous with the sarcolemma to allow ion flow.
D) The sarcolemma stores calcium, which is released upon SR depolarization.
Correct Answer: B) The sarcolemma forms T-tubules that extend deep into the fiber to
bring depolarization to the SR.
