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BIOL251 MODULE AND LAB 7 Actual Exam
2026/2027 Complete Questions and Verified
Answers with Detailed Rationales Human
Anatomy & Physiology I with Lab Grade A 100%
Correct Pass Guaranteed - A+ Graded
SECTION 1: NERVOUS SYSTEM OVERVIEW AND CELLS (Questions 1-10)
Q1: Which glial cell is responsible for myelinating axons in the central nervous system?
• A. Schwann cells
• B. Oligodendrocytes [CORRECT]
• C. Astrocytes
• D. Microglia
Correct Answer: B
Rationale: Oligodendrocytes are glial cells in the CNS that wrap around axons to form the
myelin sheath, which insulates axons and increases the speed of action potential propagation.
Unlike Schwann cells in the PNS, one oligodendrocyte can myelinate multiple axons. Astrocytes
provide structural and metabolic support, while microglia function as immune cells.
Q2: A neuron that carries sensory information from the skin to the spinal cord is classified as
which type of neuron?
• A. Motor neuron
• B. Interneuron
• C. Sensory (afferent) neuron [CORRECT]
• D. Efferent neuron
Correct Answer: C
,2
Rationale: Sensory or afferent neurons transmit signals from sensory receptors in the periphery
toward the central nervous system. Motor (efferent) neurons carry signals away from the CNS to
effectors like muscles and glands, while interneurons connect neurons within the CNS itself.
Q3: Which division of the peripheral nervous system is responsible for the "fight or flight"
response?
• A. Parasympathetic nervous system
• B. Somatic nervous system
• C. Sympathetic nervous system [CORRECT]
• D. Enteric nervous system
Correct Answer: C
Rationale: The sympathetic division of the autonomic nervous system prepares the body for
emergency situations by increasing heart rate, dilating pupils, and diverting blood flow to
skeletal muscles. The parasympathetic division mediates "rest and digest" functions, while the
somatic nervous system controls voluntary skeletal muscle movements.
Q4: Which structural component of a neuron contains the nucleus and most organelles?
• A. Axon
• B. Dendrite
• C. Axon hillock
• D. Cell body (soma) [CORRECT]
Correct Answer: D
Rationale: The cell body or soma contains the nucleus, rough endoplasmic reticulum (Nissl
bodies), mitochondria, and other organelles necessary for neuronal maintenance and function.
Dendrites receive incoming signals, the axon transmits impulses away, and the axon hillock is
the trigger zone for action potential generation.
Q5: Which glial cell type is responsible for forming the blood-brain barrier through its foot
processes?
• A. Microglia
, 3
• B. Ependymal cells
• C. Astrocytes [CORRECT]
• D. Satellite cells
Correct Answer: C
Rationale: Astrocytes extend foot processes that surround capillaries in the brain, contributing to
the formation of the blood-brain barrier which regulates the passage of substances from blood to
brain tissue. Microglia are phagocytic cells, ependymal cells produce cerebrospinal fluid, and
satellite cells support neuron cell bodies in PNS ganglia.
Q6: The autonomic nervous system is divided into sympathetic and parasympathetic divisions.
Which statement correctly describes their anatomical origins?
• A. Sympathetic is craniosacral; parasympathetic is thoracolumbar
• B. Sympathetic is thoracolumbar; parasympathetic is craniosacral [CORRECT]
• C. Both originate from thoracolumbar regions
• D. Both originate from cranial nerves only
Correct Answer: B
Rationale: The sympathetic division has thoracolumbar outflow (preganglionic fibers from T1-
L2 spinal cord segments), while the parasympathetic division has craniosacral outflow
(preganglionic fibers from cranial nerves III, VII, IX, X and sacral segments S2-S4). This
anatomical distinction is fundamental to understanding autonomic distribution and function.
Q7: Which cells in the peripheral nervous system are responsible for supporting neuron cell
bodies within ganglia?
• A. Schwann cells
• B. Oligodendrocytes
• C. Satellite cells [CORRECT]
• D. Astrocytes
Correct Answer: C
Rationale: Satellite cells surround neuron cell bodies in peripheral nervous system ganglia,
providing structural support and regulating the chemical environment around the neurons.
BIOL251 MODULE AND LAB 7 Actual Exam
2026/2027 Complete Questions and Verified
Answers with Detailed Rationales Human
Anatomy & Physiology I with Lab Grade A 100%
Correct Pass Guaranteed - A+ Graded
SECTION 1: NERVOUS SYSTEM OVERVIEW AND CELLS (Questions 1-10)
Q1: Which glial cell is responsible for myelinating axons in the central nervous system?
• A. Schwann cells
• B. Oligodendrocytes [CORRECT]
• C. Astrocytes
• D. Microglia
Correct Answer: B
Rationale: Oligodendrocytes are glial cells in the CNS that wrap around axons to form the
myelin sheath, which insulates axons and increases the speed of action potential propagation.
Unlike Schwann cells in the PNS, one oligodendrocyte can myelinate multiple axons. Astrocytes
provide structural and metabolic support, while microglia function as immune cells.
Q2: A neuron that carries sensory information from the skin to the spinal cord is classified as
which type of neuron?
• A. Motor neuron
• B. Interneuron
• C. Sensory (afferent) neuron [CORRECT]
• D. Efferent neuron
Correct Answer: C
,2
Rationale: Sensory or afferent neurons transmit signals from sensory receptors in the periphery
toward the central nervous system. Motor (efferent) neurons carry signals away from the CNS to
effectors like muscles and glands, while interneurons connect neurons within the CNS itself.
Q3: Which division of the peripheral nervous system is responsible for the "fight or flight"
response?
• A. Parasympathetic nervous system
• B. Somatic nervous system
• C. Sympathetic nervous system [CORRECT]
• D. Enteric nervous system
Correct Answer: C
Rationale: The sympathetic division of the autonomic nervous system prepares the body for
emergency situations by increasing heart rate, dilating pupils, and diverting blood flow to
skeletal muscles. The parasympathetic division mediates "rest and digest" functions, while the
somatic nervous system controls voluntary skeletal muscle movements.
Q4: Which structural component of a neuron contains the nucleus and most organelles?
• A. Axon
• B. Dendrite
• C. Axon hillock
• D. Cell body (soma) [CORRECT]
Correct Answer: D
Rationale: The cell body or soma contains the nucleus, rough endoplasmic reticulum (Nissl
bodies), mitochondria, and other organelles necessary for neuronal maintenance and function.
Dendrites receive incoming signals, the axon transmits impulses away, and the axon hillock is
the trigger zone for action potential generation.
Q5: Which glial cell type is responsible for forming the blood-brain barrier through its foot
processes?
• A. Microglia
, 3
• B. Ependymal cells
• C. Astrocytes [CORRECT]
• D. Satellite cells
Correct Answer: C
Rationale: Astrocytes extend foot processes that surround capillaries in the brain, contributing to
the formation of the blood-brain barrier which regulates the passage of substances from blood to
brain tissue. Microglia are phagocytic cells, ependymal cells produce cerebrospinal fluid, and
satellite cells support neuron cell bodies in PNS ganglia.
Q6: The autonomic nervous system is divided into sympathetic and parasympathetic divisions.
Which statement correctly describes their anatomical origins?
• A. Sympathetic is craniosacral; parasympathetic is thoracolumbar
• B. Sympathetic is thoracolumbar; parasympathetic is craniosacral [CORRECT]
• C. Both originate from thoracolumbar regions
• D. Both originate from cranial nerves only
Correct Answer: B
Rationale: The sympathetic division has thoracolumbar outflow (preganglionic fibers from T1-
L2 spinal cord segments), while the parasympathetic division has craniosacral outflow
(preganglionic fibers from cranial nerves III, VII, IX, X and sacral segments S2-S4). This
anatomical distinction is fundamental to understanding autonomic distribution and function.
Q7: Which cells in the peripheral nervous system are responsible for supporting neuron cell
bodies within ganglia?
• A. Schwann cells
• B. Oligodendrocytes
• C. Satellite cells [CORRECT]
• D. Astrocytes
Correct Answer: C
Rationale: Satellite cells surround neuron cell bodies in peripheral nervous system ganglia,
providing structural support and regulating the chemical environment around the neurons.
