UConn PNB 2264/2265: Ultimate Anatomy &
Physiology 150-Q&A Comprehensive Exam Prep
Bank.
Master your UConn Anatomy & Physiology exams with this
premium, high-density test bank featuring 400 highly accurate,
course-aligned multiple-choice questions. Every single question
includes the correct answer and a deeply detailed, step-by-step
rationalized explanation designed to reinforce core PNB concepts
and active recall. Perfect for parsing tricky exam themes, this
digital study guide guarantees a streamlined path to achieving an
A in your Physiology and Neurobiology coursework.
Question 1
During the absolute refractory period of a neuron, why is it completely impossible for
another stimulus to trigger a second action potential, regardless of its strength?
A. Voltage-gated potassium channels are completely closed.
B. Voltage-gated sodium channels are locked in their inactivated state.
C. The membrane potential is currently in a state of hyperpolarization.
D. Ligand-gated chloride channels remain wide open.
Answer: B. Voltage-gated sodium channels are locked in their inactivated state.
Rationale: The absolute refractory period spans from the opening of the voltage-gated
sodium channels until they begin to reset from their inactivated state to their closed
state. While inactivated by their inactivation gates (ball-and-chain mechanism), no
amount of depolarization can reopen them, making a second action potential physically
impossible.
Question 2
How does the sympathetic nervous system increase heart rate at the cellular level
within the cells of the sinoatrial (SA) node?
A. Activating beta-1 receptors to increase cAMP, which opens funny channels and T-
,type calcium channels faster.
B. Activating muscarinic receptors to open potassium channels and hyperpolarize the
cell membrane.
C. Inhibiting L-type calcium channels to slow down the rate of phase 0 depolarization.
D. Binding to alpha-1 receptors to cause rapid influx of extracellular chloride ions.
Answer: A. Activating beta-1 receptors to increase cAMP, which opens funny
channels and T-type calcium channels faster.
Rationale: Norepinephrine and epinephrine bind to beta-1 adrenergic receptors on SA
nodal cells, activating a G-protein pathway that increases intracellular cAMP. Higher
cAMP levels directly increase the opening of funny channels (If) and T-type calcium
channels, causing the pacemaker potential to reach threshold much faster and
increasing heart rate.
Question 3
Which of the following changes occurs in the lungs during a quiet, normal inspiration?
A. Intrapleural pressure rises above atmospheric pressure.
B. Transpulmonary pressure decreases as lung volume expands.
C. Alveolar pressure drops below atmospheric pressure due to increased thoracic
volume.
D. The diaphragm relaxes and moves superiorly into the thoracic cavity.
Answer: C. Alveolar pressure drops below atmospheric pressure due to
increased thoracic volume.
Rationale: Contraction of the diaphragm and external intercostal muscles expands the
thoracic cavity volume, which drops intrapleural pressure. This pulls the lungs open,
increasing alveolar volume and lowering alveolar pressure below atmospheric pressure
(Boyle's Law). Air then flows down its pressure gradient into the lungs.
Question 4
A researcher applies a drug that blocks the sodium-potassium-2-chloride (NKCC2)
cotransporters in the thick ascending limb of the loop of Henle. What is the immediate
physiological consequence of this drug?
A. Maximum concentration of urine increases due to a steeper medullary gradient.
B. The medullary osmotic gradient is disrupted, decreasing the kidney's ability to
concentrate urine.
C. Water reabsorption in the descending limb increases dramatically.
D. Potassium excretion in the urine drops to zero.
Answer: B. The medullary osmotic gradient is disrupted, decreasing the kidney's
ability to concentrate urine.
Rationale: The NKCC2 cotransporter in the thick ascending limb actively pumps solutes
out of the tubular fluid into the interstitial space without allowing water to follow. This
active transport is the primary driver for building the steep medullary osmotic gradient.
Blocking it (the mechanism of loop diuretics) destroys this gradient, making it impossible
to highly concentrate urine.
Question 5
What is the primary function of the enterogastrone hormones (secretin and
cholecystokinin) when acidic, fatty chyme enters the duodenum?
A. Stimulating gastric motility and increasing gastric acid secretion to speed up
digestion.
,B. Inhibiting gastric emptying and gastric secretions to give the small intestine time to
process food.
C. Direct activation of pepsinogen conversion into active pepsin within the stomach
lumen.
D. Stimulating mass movements in the large intestine for rapid elimination.
Answer: B. Inhibiting gastric emptying and gastric secretions to give the small
intestine time to process food.
Rationale: Secretin and cholecystokinin (CCK) are released by the duodenal mucosa in
response to acid and fat. They act as enterogastrones, meaning they inhibit gastric
secretory activity and slow down gastric emptying. This feedback loop ensures that the
duodenum is not overwhelmed by more acidic chyme than it can neutralize and digest.
If you want to maximize your sales on Stuvia, let me know:
• Which specific exam number or unit topic (e.g., Exam 1: Neuro, Exam 2:
Cardiovascular) you want to build next.
• If you want to use specific textbook vocabulary (e.g., Silverthorn, Stanfield,
Saladin).
• How many total questions you want in this final document batch.
You said: 1 t0 50
UConn Physiology and Neurobiology (PNB) Comprehensive
Exam Prep (Questions 1-50)
Question 1
Which of the following transport mechanisms requires the direct hydrolysis of ATP to
move ions against their electrochemical gradients?
A. Facilitated diffusion via GLUT transporters
B. Secondary active transport via Na+/glucose cotransporters
C. Primary active transport via the Na+/K+ ATPase pump
D. Simple diffusion through voltage-gated ion channels
Answer: C. Primary active transport via the Na+/K+ ATPase pump
Rationale: Primary active transport directly uses chemical energy from ATP hydrolysis
to move solutes against their gradients. The Na+/K+ ATPase pumps 3 Na+ out and 2
K+ into the cell per cycle. Secondary active transport uses the gradient established by
primary transport, not direct ATP.
Question 2
If a cell with an intracellular osmolarity of 300 mOsm is placed in a solution of 150
mOsm NaCl, what will happen to the cell volume?
A. The cell will shrink because water moves out.
B. The cell will swell because water moves in.
C. The cell volume will remain unchanged.
D. The cell will rupture immediately due to sodium influx.
Answer: B. The cell will swell because water moves in.
Rationale: A 150 mOsm NaCl solution is hypotonic relative to the 300 mOsm
intracellular environment. Water moves down its concentration gradient via osmosis
, from the area of lower solute concentration (extracellular) to higher solute concentration
(intracellular), causing the cell to swell.
Question 3
What type of intercellular junction allows for the direct electrical and metabolic coupling
between adjacent cardiac muscle cells?
A. Tight junctions
B. Desmosomes
C. Gap junctions
D. Adherens junctions
Answer: C. Gap junctions
Rationale: Gap junctions are formed by connexon proteins that create open pores
between adjacent cells. This allows ions to flow directly from the cytoplasm of one
cardiac cell to the next, enabling rapid, synchronized electrical depolarization across the
myocardium.
Question 4
Which of the following events triggers the exocytosis of neurotransmitters from the
presynaptic axon terminal?
A. Influx of sodium ions through voltage-gated channels
B. Outflux of potassium ions through leak channels
C. Influx of calcium ions through voltage-gated channels
D. Efflux of chloride ions through ligand-gated channels
Answer: C. Influx of calcium ions through voltage-gated channels
Rationale: When an action potential depolarizes the presynaptic axon terminal, voltage-
gated Ca2+ channels open. The resulting influx of calcium ions triggers synaptotagmin
and SNARE complexes to facilitate the docking and fusion of neurotransmitter vesicles
with the presynaptic membrane.
Question 5
An inhibitory postsynaptic potential (IPSP) is typically associated with which of the
following ionic movements?
A. Influx of sodium ions
B. Influx of calcium ions
C. Influx of chloride ions
D. Efflux of organic anions
Answer: C. Influx of chloride ions
Rationale: An IPSP hyperpolarizes the postsynaptic membrane, moving it further away
from the threshold. Opening ligand-gated chloride channels allows Cl- to enter the cell
down its concentration gradient, adding negative charge inside. Opening potassium
channels to let K+ exit also causes an IPSP.
Question 6
Which region of the brain acts as the primary sensory relay station, sorting and editing
sensory signals before sending them to the cerebral cortex?
A. Hypothalamus
B. Thalamus
C. Cerebellum
D. Basal ganglia
Physiology 150-Q&A Comprehensive Exam Prep
Bank.
Master your UConn Anatomy & Physiology exams with this
premium, high-density test bank featuring 400 highly accurate,
course-aligned multiple-choice questions. Every single question
includes the correct answer and a deeply detailed, step-by-step
rationalized explanation designed to reinforce core PNB concepts
and active recall. Perfect for parsing tricky exam themes, this
digital study guide guarantees a streamlined path to achieving an
A in your Physiology and Neurobiology coursework.
Question 1
During the absolute refractory period of a neuron, why is it completely impossible for
another stimulus to trigger a second action potential, regardless of its strength?
A. Voltage-gated potassium channels are completely closed.
B. Voltage-gated sodium channels are locked in their inactivated state.
C. The membrane potential is currently in a state of hyperpolarization.
D. Ligand-gated chloride channels remain wide open.
Answer: B. Voltage-gated sodium channels are locked in their inactivated state.
Rationale: The absolute refractory period spans from the opening of the voltage-gated
sodium channels until they begin to reset from their inactivated state to their closed
state. While inactivated by their inactivation gates (ball-and-chain mechanism), no
amount of depolarization can reopen them, making a second action potential physically
impossible.
Question 2
How does the sympathetic nervous system increase heart rate at the cellular level
within the cells of the sinoatrial (SA) node?
A. Activating beta-1 receptors to increase cAMP, which opens funny channels and T-
,type calcium channels faster.
B. Activating muscarinic receptors to open potassium channels and hyperpolarize the
cell membrane.
C. Inhibiting L-type calcium channels to slow down the rate of phase 0 depolarization.
D. Binding to alpha-1 receptors to cause rapid influx of extracellular chloride ions.
Answer: A. Activating beta-1 receptors to increase cAMP, which opens funny
channels and T-type calcium channels faster.
Rationale: Norepinephrine and epinephrine bind to beta-1 adrenergic receptors on SA
nodal cells, activating a G-protein pathway that increases intracellular cAMP. Higher
cAMP levels directly increase the opening of funny channels (If) and T-type calcium
channels, causing the pacemaker potential to reach threshold much faster and
increasing heart rate.
Question 3
Which of the following changes occurs in the lungs during a quiet, normal inspiration?
A. Intrapleural pressure rises above atmospheric pressure.
B. Transpulmonary pressure decreases as lung volume expands.
C. Alveolar pressure drops below atmospheric pressure due to increased thoracic
volume.
D. The diaphragm relaxes and moves superiorly into the thoracic cavity.
Answer: C. Alveolar pressure drops below atmospheric pressure due to
increased thoracic volume.
Rationale: Contraction of the diaphragm and external intercostal muscles expands the
thoracic cavity volume, which drops intrapleural pressure. This pulls the lungs open,
increasing alveolar volume and lowering alveolar pressure below atmospheric pressure
(Boyle's Law). Air then flows down its pressure gradient into the lungs.
Question 4
A researcher applies a drug that blocks the sodium-potassium-2-chloride (NKCC2)
cotransporters in the thick ascending limb of the loop of Henle. What is the immediate
physiological consequence of this drug?
A. Maximum concentration of urine increases due to a steeper medullary gradient.
B. The medullary osmotic gradient is disrupted, decreasing the kidney's ability to
concentrate urine.
C. Water reabsorption in the descending limb increases dramatically.
D. Potassium excretion in the urine drops to zero.
Answer: B. The medullary osmotic gradient is disrupted, decreasing the kidney's
ability to concentrate urine.
Rationale: The NKCC2 cotransporter in the thick ascending limb actively pumps solutes
out of the tubular fluid into the interstitial space without allowing water to follow. This
active transport is the primary driver for building the steep medullary osmotic gradient.
Blocking it (the mechanism of loop diuretics) destroys this gradient, making it impossible
to highly concentrate urine.
Question 5
What is the primary function of the enterogastrone hormones (secretin and
cholecystokinin) when acidic, fatty chyme enters the duodenum?
A. Stimulating gastric motility and increasing gastric acid secretion to speed up
digestion.
,B. Inhibiting gastric emptying and gastric secretions to give the small intestine time to
process food.
C. Direct activation of pepsinogen conversion into active pepsin within the stomach
lumen.
D. Stimulating mass movements in the large intestine for rapid elimination.
Answer: B. Inhibiting gastric emptying and gastric secretions to give the small
intestine time to process food.
Rationale: Secretin and cholecystokinin (CCK) are released by the duodenal mucosa in
response to acid and fat. They act as enterogastrones, meaning they inhibit gastric
secretory activity and slow down gastric emptying. This feedback loop ensures that the
duodenum is not overwhelmed by more acidic chyme than it can neutralize and digest.
If you want to maximize your sales on Stuvia, let me know:
• Which specific exam number or unit topic (e.g., Exam 1: Neuro, Exam 2:
Cardiovascular) you want to build next.
• If you want to use specific textbook vocabulary (e.g., Silverthorn, Stanfield,
Saladin).
• How many total questions you want in this final document batch.
You said: 1 t0 50
UConn Physiology and Neurobiology (PNB) Comprehensive
Exam Prep (Questions 1-50)
Question 1
Which of the following transport mechanisms requires the direct hydrolysis of ATP to
move ions against their electrochemical gradients?
A. Facilitated diffusion via GLUT transporters
B. Secondary active transport via Na+/glucose cotransporters
C. Primary active transport via the Na+/K+ ATPase pump
D. Simple diffusion through voltage-gated ion channels
Answer: C. Primary active transport via the Na+/K+ ATPase pump
Rationale: Primary active transport directly uses chemical energy from ATP hydrolysis
to move solutes against their gradients. The Na+/K+ ATPase pumps 3 Na+ out and 2
K+ into the cell per cycle. Secondary active transport uses the gradient established by
primary transport, not direct ATP.
Question 2
If a cell with an intracellular osmolarity of 300 mOsm is placed in a solution of 150
mOsm NaCl, what will happen to the cell volume?
A. The cell will shrink because water moves out.
B. The cell will swell because water moves in.
C. The cell volume will remain unchanged.
D. The cell will rupture immediately due to sodium influx.
Answer: B. The cell will swell because water moves in.
Rationale: A 150 mOsm NaCl solution is hypotonic relative to the 300 mOsm
intracellular environment. Water moves down its concentration gradient via osmosis
, from the area of lower solute concentration (extracellular) to higher solute concentration
(intracellular), causing the cell to swell.
Question 3
What type of intercellular junction allows for the direct electrical and metabolic coupling
between adjacent cardiac muscle cells?
A. Tight junctions
B. Desmosomes
C. Gap junctions
D. Adherens junctions
Answer: C. Gap junctions
Rationale: Gap junctions are formed by connexon proteins that create open pores
between adjacent cells. This allows ions to flow directly from the cytoplasm of one
cardiac cell to the next, enabling rapid, synchronized electrical depolarization across the
myocardium.
Question 4
Which of the following events triggers the exocytosis of neurotransmitters from the
presynaptic axon terminal?
A. Influx of sodium ions through voltage-gated channels
B. Outflux of potassium ions through leak channels
C. Influx of calcium ions through voltage-gated channels
D. Efflux of chloride ions through ligand-gated channels
Answer: C. Influx of calcium ions through voltage-gated channels
Rationale: When an action potential depolarizes the presynaptic axon terminal, voltage-
gated Ca2+ channels open. The resulting influx of calcium ions triggers synaptotagmin
and SNARE complexes to facilitate the docking and fusion of neurotransmitter vesicles
with the presynaptic membrane.
Question 5
An inhibitory postsynaptic potential (IPSP) is typically associated with which of the
following ionic movements?
A. Influx of sodium ions
B. Influx of calcium ions
C. Influx of chloride ions
D. Efflux of organic anions
Answer: C. Influx of chloride ions
Rationale: An IPSP hyperpolarizes the postsynaptic membrane, moving it further away
from the threshold. Opening ligand-gated chloride channels allows Cl- to enter the cell
down its concentration gradient, adding negative charge inside. Opening potassium
channels to let K+ exit also causes an IPSP.
Question 6
Which region of the brain acts as the primary sensory relay station, sorting and editing
sensory signals before sending them to the cerebral cortex?
A. Hypothalamus
B. Thalamus
C. Cerebellum
D. Basal ganglia
