BIO 225 TEST PAPER 2025/2026 QUESTIONS AND
SOLUTIONS GRADED A+ TIP
✔✔Brace/protect neurons
Phagocytes (microglia)
Myelinate the cyto-plasmic extensions of the neurons
Role in capillary-neuorn exchange
Control the chemical environment around neurons (astrocytes) - ✔✔5 Functions of
Neuroglia
✔✔Cell Body - ✔✔contains the nucleus and processes extend out from it. Makes up the
gray matter of the CNS.
✔✔Nuclei - ✔✔collection of cell bodies within the CNS.
✔✔Ganglia - ✔✔collection of cell bodies outside the CNS.
✔✔Neurofibrils - ✔✔cytoskeletal elements of the neuron. Important in support and
intracellular transport.
✔✔Nissi Bodies - ✔✔elaborate type of endoplasmic reticulum, involved in metabolic
activities.
✔✔Dendrites - ✔✔receptive regions
✔✔Axons - ✔✔nerve impulse generators and transmitters.
✔✔Axon Collaterals - ✔✔branches of the axon.
✔✔Axon Hillock - ✔✔slightly enlarged cell body structure where axon begins.
✔✔Axonal Terminals - ✔✔ends of axon that are in the effector (muscle, organ, gland,
etc.)
✔✔Synaptic Cleft - ✔✔fluid filled gap between axonal terminals and the cell body or
dendrites of the next neuron or between the axonal terminals and the effector.
✔✔Myelin Sheath - ✔✔tight core of plasma membrane material encompassing the
axon; created from the Schwann Cells in the PNS and Oligodendrocytes in the CNS.
✔✔Nodes of Ranvier - ✔✔gaps in the myelin sheath (between Schwann cells)
✔✔Unipolar Neurons - ✔✔one very short process extends from cell body, which divides
into peripheral and central processes, extending from cell body. Functionally only the
, most distal portions of the peripheral process act as dendrites, the rest of the peripheral
and central processes act as an axon. Nearly all neurons that conduct impulses toward
the CNS are
✔✔Bipolar Neurons - ✔✔have two processes attached to the cell body, an axon and a
dendrite, which are attached to the cell doby. Quite rare type of neuron. Found in part of
the receptor apparatus of the eye, ear, and olfactory mucosa.
✔✔Multipolar Neurons - ✔✔many processes extending from the cell body are classified
as dendrites and one single process is the axon. Most neurons in the CNS and those
that carry impulses away from the CNS are classified as
✔✔Afferent (sensory) neurons - ✔✔carry impulses from sensory receptors in the
internal organs, skin, skeletal muscle, joints, or special sensory organs to the CNS. Cell
bodies always found in ganglia outside CNS. Typically unipolar neurons.
✔✔Efferent (motor) neurons - ✔✔carrying impulses from CNS to the visceraperipheral
body; cell body (nuclei) found in CNS.
✔✔Interneurons - ✔✔found between sensory and motor neurons; connects the
pathway; cell body found in CNS.
✔✔Mixed Nerves - ✔✔carry both sensory (afferent) and motor (efferent) fibers. All
spinal nerves and majority of cranial nerves are mixed nerves.
✔✔Sensory (afferent) nerves - ✔✔carry only sensory processes; conduct impulses
toward CNS***Almost all nerves conducting impulses toward the CNS are sensory
nerves. A few Cranial nerves are pure sensory.
✔✔Motor (efferent) nerves - ✔✔carry only motor processes; conduct impulses away
from CNS***Ventral roots of the spinal cord are an example of motor nerves.
✔✔Endoneurium - ✔✔delicate CT sheath that surrounds each individual nerve fiber
within a nerve
✔✔Fascicles - ✔✔group of nerve fibers bound together surrounded by perineurium.
✔✔Perineurium - ✔✔coarse CT that surrounds a a group of fibers to form a bundle of
fibers (fascicle)
✔✔Epineurium - ✔✔white, fibrous CT that surrounds a group of nerve fascicles
✔✔Myofilament - ✔✔Actin or myosin containing structure
SOLUTIONS GRADED A+ TIP
✔✔Brace/protect neurons
Phagocytes (microglia)
Myelinate the cyto-plasmic extensions of the neurons
Role in capillary-neuorn exchange
Control the chemical environment around neurons (astrocytes) - ✔✔5 Functions of
Neuroglia
✔✔Cell Body - ✔✔contains the nucleus and processes extend out from it. Makes up the
gray matter of the CNS.
✔✔Nuclei - ✔✔collection of cell bodies within the CNS.
✔✔Ganglia - ✔✔collection of cell bodies outside the CNS.
✔✔Neurofibrils - ✔✔cytoskeletal elements of the neuron. Important in support and
intracellular transport.
✔✔Nissi Bodies - ✔✔elaborate type of endoplasmic reticulum, involved in metabolic
activities.
✔✔Dendrites - ✔✔receptive regions
✔✔Axons - ✔✔nerve impulse generators and transmitters.
✔✔Axon Collaterals - ✔✔branches of the axon.
✔✔Axon Hillock - ✔✔slightly enlarged cell body structure where axon begins.
✔✔Axonal Terminals - ✔✔ends of axon that are in the effector (muscle, organ, gland,
etc.)
✔✔Synaptic Cleft - ✔✔fluid filled gap between axonal terminals and the cell body or
dendrites of the next neuron or between the axonal terminals and the effector.
✔✔Myelin Sheath - ✔✔tight core of plasma membrane material encompassing the
axon; created from the Schwann Cells in the PNS and Oligodendrocytes in the CNS.
✔✔Nodes of Ranvier - ✔✔gaps in the myelin sheath (between Schwann cells)
✔✔Unipolar Neurons - ✔✔one very short process extends from cell body, which divides
into peripheral and central processes, extending from cell body. Functionally only the
, most distal portions of the peripheral process act as dendrites, the rest of the peripheral
and central processes act as an axon. Nearly all neurons that conduct impulses toward
the CNS are
✔✔Bipolar Neurons - ✔✔have two processes attached to the cell body, an axon and a
dendrite, which are attached to the cell doby. Quite rare type of neuron. Found in part of
the receptor apparatus of the eye, ear, and olfactory mucosa.
✔✔Multipolar Neurons - ✔✔many processes extending from the cell body are classified
as dendrites and one single process is the axon. Most neurons in the CNS and those
that carry impulses away from the CNS are classified as
✔✔Afferent (sensory) neurons - ✔✔carry impulses from sensory receptors in the
internal organs, skin, skeletal muscle, joints, or special sensory organs to the CNS. Cell
bodies always found in ganglia outside CNS. Typically unipolar neurons.
✔✔Efferent (motor) neurons - ✔✔carrying impulses from CNS to the visceraperipheral
body; cell body (nuclei) found in CNS.
✔✔Interneurons - ✔✔found between sensory and motor neurons; connects the
pathway; cell body found in CNS.
✔✔Mixed Nerves - ✔✔carry both sensory (afferent) and motor (efferent) fibers. All
spinal nerves and majority of cranial nerves are mixed nerves.
✔✔Sensory (afferent) nerves - ✔✔carry only sensory processes; conduct impulses
toward CNS***Almost all nerves conducting impulses toward the CNS are sensory
nerves. A few Cranial nerves are pure sensory.
✔✔Motor (efferent) nerves - ✔✔carry only motor processes; conduct impulses away
from CNS***Ventral roots of the spinal cord are an example of motor nerves.
✔✔Endoneurium - ✔✔delicate CT sheath that surrounds each individual nerve fiber
within a nerve
✔✔Fascicles - ✔✔group of nerve fibers bound together surrounded by perineurium.
✔✔Perineurium - ✔✔coarse CT that surrounds a a group of fibers to form a bundle of
fibers (fascicle)
✔✔Epineurium - ✔✔white, fibrous CT that surrounds a group of nerve fascicles
✔✔Myofilament - ✔✔Actin or myosin containing structure
