BIOL251 HUMAN ANATOMY & PHYSIOLOGY I W/LAB 2026 STUDY
GUIDE | TESTBANK | PRACTICE QUESTIONS & ANSWERS |
COMPREHENSIVE PRACTICE EXAM | ADVANCED REVIEW | EXAM
PREPARATION | LATEST UPDATE 2026/2027
Examiner:
Portage Learning (Practice Examination Based on BIOL251 Human Anatomy
& Physiology I with Lab Course Topics)
TABLE OF CONTENTS
1. Integumentary System
2. Skeletal Tissue and Bone Physiology
3. Axial and Appendicular Skeleton
4. Articulations and Joint Mechanics
5. Muscle Tissue Physiology
6. Skeletal Muscle Anatomy and Function
7. Neuromuscular Junction and Excitation-Contraction Coupling
8. Nervous Tissue and Neurophysiology
9. Spinal Cord and Peripheral Nervous System
10.Integrated Anatomy & Physiology Applications
CELLULAR PHYSIOLOGY || TISSUE HISTOLOGY || HOMEOSTASIS
|| INTEGUMENTARY SYSTEM || BONE REMODELING || AXIAL
SKELETON || APPENDICULAR SKELETON || JOINT
BIOMECHANICS || MUSCLE CONTRACTION || NEUROMUSCULAR
JUNCTION || MEMBRANE POTENTIALS || ACTION POTENTIALS ||
PERIPHERAL NERVOUS SYSTEM || SPINAL REFLEXES || CRANIAL
NERVES || AUTONOMIC NERVOUS SYSTEM || CLINICAL
APPLICATIONS || LAB INTERPRETATION || STRUCTURE AND
FUNCTION || EXAM PREPARATION
QUESTION 1.
A patient has a mutation that prevents osteoclasts from secreting hydrogen ions
into the resorption lacuna. Which physiological consequence would most likely
occur over time?
,A. Increased bone density with impaired bone remodeling
B. Accelerated calcium release into the bloodstream
C. Decreased osteoblast differentiation due to excessive collagen degradation
D. Increased endochondral ossification throughout adulthood
🔴 Correct Answer: A. Increased bone density with impaired bone
remodeling
🔵 Explanation: Osteoclasts require an acidic environment to dissolve
hydroxyapatite during bone resorption. Failure to acidify the resorption lacuna
limits bone turnover, resulting in abnormally dense but poorly remodeled bone.
The remaining options describe processes that either require normal osteoclast
activity or occur during development rather than adulthood.
────────────────────────────────────────
QUESTION 2.
During a laboratory investigation, skeletal muscle fibers are exposed to a drug
that blocks voltage-gated calcium channels in the motor neuron terminal. Which
event is most directly inhibited?
A. Troponin binding to calcium
B. Acetylcholine release into the synaptic cleft
C. ATP hydrolysis by myosin
D. Sodium influx through nicotinic receptors
🔴 Correct Answer: B. Acetylcholine release into the synaptic cleft
🔵 Explanation: Calcium entering the presynaptic terminal triggers synaptic
vesicle fusion and acetylcholine exocytosis. Without calcium influx,
neurotransmitter release fails, preventing downstream muscle activation. The
remaining events occur after acetylcholine has already been released.
────────────────────────────────────────
QUESTION 3.
A researcher selectively damages fibrocartilage while preserving hyaline and
elastic cartilage. Which structure would most likely exhibit impaired function?
,A. Costal cartilage
B. Tracheal rings
C. Pubic symphysis
D. Epiglottis
🔴 Correct Answer: C. Pubic symphysis
🔵 Explanation: Fibrocartilage provides exceptional resistance to compression
and tensile stress and is found in structures such as the pubic symphysis and
intervertebral discs. Costal cartilage and tracheal rings contain hyaline
cartilage, while the epiglottis is composed primarily of elastic cartilage.
────────────────────────────────────────
QUESTION 4.
A patient sustains trauma to the radial nerve. Which movement would most
likely be significantly impaired?
A. Plantar flexion of the foot
B. Extension of the wrist
C. Flexion of the knee
D. Adduction of the thigh
🔴 Correct Answer: B. Extension of the wrist
🔵 Explanation: The radial nerve innervates the posterior compartment of the
arm and forearm, including the wrist extensors. Injury commonly produces
wrist drop due to loss of extension. The other movements are controlled by
different peripheral nerves.
────────────────────────────────────────
QUESTION 5.
Which change would most directly decrease the velocity of action potential
propagation in a myelinated axon?
A. Increased diameter of the axon
B. Increased internodal distance within physiological limits
, C. Loss of myelin surrounding the axon
D. Increased sodium channel density at nodes of Ranvier
🔴 Correct Answer: C. Loss of myelin surrounding the axon
🔵 Explanation: Myelin enables saltatory conduction by insulating the axon
and allowing action potentials to jump between nodes of Ranvier.
Demyelination slows conduction and may ultimately block impulse
transmission. The remaining options generally increase or preserve conduction
velocity.
────────────────────────────────────────
QUESTION 6.
An investigator measures the resting membrane potential of a neuron
immediately after complete inhibition of the sodium-potassium ATPase. Which
outcome is most likely if sufficient time passes?
A. The resting membrane potential gradually dissipates
B. The membrane immediately depolarizes to +30 mV
C. Action potentials become larger than normal
D. Potassium equilibrium potential becomes more negative
🔴 Correct Answer: A. The resting membrane potential gradually
dissipates
🔵 Explanation: The sodium-potassium ATPase maintains ionic gradients
required for resting membrane potential. Without continued transport, sodium
and potassium gradients slowly collapse, reducing the membrane potential.
Immediate depolarization to action potential levels does not occur solely
because the pump stops.
────────────────────────────────────────
QUESTION 7.
A fracture occurs through the epiphyseal plate of a growing adolescent. Which
process is at greatest risk of disruption?
GUIDE | TESTBANK | PRACTICE QUESTIONS & ANSWERS |
COMPREHENSIVE PRACTICE EXAM | ADVANCED REVIEW | EXAM
PREPARATION | LATEST UPDATE 2026/2027
Examiner:
Portage Learning (Practice Examination Based on BIOL251 Human Anatomy
& Physiology I with Lab Course Topics)
TABLE OF CONTENTS
1. Integumentary System
2. Skeletal Tissue and Bone Physiology
3. Axial and Appendicular Skeleton
4. Articulations and Joint Mechanics
5. Muscle Tissue Physiology
6. Skeletal Muscle Anatomy and Function
7. Neuromuscular Junction and Excitation-Contraction Coupling
8. Nervous Tissue and Neurophysiology
9. Spinal Cord and Peripheral Nervous System
10.Integrated Anatomy & Physiology Applications
CELLULAR PHYSIOLOGY || TISSUE HISTOLOGY || HOMEOSTASIS
|| INTEGUMENTARY SYSTEM || BONE REMODELING || AXIAL
SKELETON || APPENDICULAR SKELETON || JOINT
BIOMECHANICS || MUSCLE CONTRACTION || NEUROMUSCULAR
JUNCTION || MEMBRANE POTENTIALS || ACTION POTENTIALS ||
PERIPHERAL NERVOUS SYSTEM || SPINAL REFLEXES || CRANIAL
NERVES || AUTONOMIC NERVOUS SYSTEM || CLINICAL
APPLICATIONS || LAB INTERPRETATION || STRUCTURE AND
FUNCTION || EXAM PREPARATION
QUESTION 1.
A patient has a mutation that prevents osteoclasts from secreting hydrogen ions
into the resorption lacuna. Which physiological consequence would most likely
occur over time?
,A. Increased bone density with impaired bone remodeling
B. Accelerated calcium release into the bloodstream
C. Decreased osteoblast differentiation due to excessive collagen degradation
D. Increased endochondral ossification throughout adulthood
🔴 Correct Answer: A. Increased bone density with impaired bone
remodeling
🔵 Explanation: Osteoclasts require an acidic environment to dissolve
hydroxyapatite during bone resorption. Failure to acidify the resorption lacuna
limits bone turnover, resulting in abnormally dense but poorly remodeled bone.
The remaining options describe processes that either require normal osteoclast
activity or occur during development rather than adulthood.
────────────────────────────────────────
QUESTION 2.
During a laboratory investigation, skeletal muscle fibers are exposed to a drug
that blocks voltage-gated calcium channels in the motor neuron terminal. Which
event is most directly inhibited?
A. Troponin binding to calcium
B. Acetylcholine release into the synaptic cleft
C. ATP hydrolysis by myosin
D. Sodium influx through nicotinic receptors
🔴 Correct Answer: B. Acetylcholine release into the synaptic cleft
🔵 Explanation: Calcium entering the presynaptic terminal triggers synaptic
vesicle fusion and acetylcholine exocytosis. Without calcium influx,
neurotransmitter release fails, preventing downstream muscle activation. The
remaining events occur after acetylcholine has already been released.
────────────────────────────────────────
QUESTION 3.
A researcher selectively damages fibrocartilage while preserving hyaline and
elastic cartilage. Which structure would most likely exhibit impaired function?
,A. Costal cartilage
B. Tracheal rings
C. Pubic symphysis
D. Epiglottis
🔴 Correct Answer: C. Pubic symphysis
🔵 Explanation: Fibrocartilage provides exceptional resistance to compression
and tensile stress and is found in structures such as the pubic symphysis and
intervertebral discs. Costal cartilage and tracheal rings contain hyaline
cartilage, while the epiglottis is composed primarily of elastic cartilage.
────────────────────────────────────────
QUESTION 4.
A patient sustains trauma to the radial nerve. Which movement would most
likely be significantly impaired?
A. Plantar flexion of the foot
B. Extension of the wrist
C. Flexion of the knee
D. Adduction of the thigh
🔴 Correct Answer: B. Extension of the wrist
🔵 Explanation: The radial nerve innervates the posterior compartment of the
arm and forearm, including the wrist extensors. Injury commonly produces
wrist drop due to loss of extension. The other movements are controlled by
different peripheral nerves.
────────────────────────────────────────
QUESTION 5.
Which change would most directly decrease the velocity of action potential
propagation in a myelinated axon?
A. Increased diameter of the axon
B. Increased internodal distance within physiological limits
, C. Loss of myelin surrounding the axon
D. Increased sodium channel density at nodes of Ranvier
🔴 Correct Answer: C. Loss of myelin surrounding the axon
🔵 Explanation: Myelin enables saltatory conduction by insulating the axon
and allowing action potentials to jump between nodes of Ranvier.
Demyelination slows conduction and may ultimately block impulse
transmission. The remaining options generally increase or preserve conduction
velocity.
────────────────────────────────────────
QUESTION 6.
An investigator measures the resting membrane potential of a neuron
immediately after complete inhibition of the sodium-potassium ATPase. Which
outcome is most likely if sufficient time passes?
A. The resting membrane potential gradually dissipates
B. The membrane immediately depolarizes to +30 mV
C. Action potentials become larger than normal
D. Potassium equilibrium potential becomes more negative
🔴 Correct Answer: A. The resting membrane potential gradually
dissipates
🔵 Explanation: The sodium-potassium ATPase maintains ionic gradients
required for resting membrane potential. Without continued transport, sodium
and potassium gradients slowly collapse, reducing the membrane potential.
Immediate depolarization to action potential levels does not occur solely
because the pump stops.
────────────────────────────────────────
QUESTION 7.
A fracture occurs through the epiphyseal plate of a growing adolescent. Which
process is at greatest risk of disruption?
