BIOL 251 Module 6 Exam: Nervous System I | Action Potentials, Neuroglia & Brain Anatomy Review| Module 6: Nervous System I (CNS)|Questions and Answers plus Explanation| pdf

BIOL 251 Module 6 Exam: Nervous System I | Action
Potentials, Neuroglia & Brain Anatomy Review| Module 6:
Nervous System I (CNS)|Questions and Answers plus
Explanation| pdf

Part 1: Nervous Tissue & Neuroglia
1. Which division of the nervous system consists specifically of the brain and
spinal cord?
 A) Peripheral Nervous System (PNS)

 B) Central Nervous System (CNS)

 C) Autonomic Nervous System (ANS)

 D) Somatic Nervous System

Explanation: The CNS is the integrating and control center of the nervous system. All
other nervous structures belong to the PNS.
2. Which neuroglia (glial cell) is responsible for forming the "Blood-Brain
Barrier"?
 A) Microglia

 B) Ependymal cells

 C) Astrocytes

 D) Oligodendrocytes

Explanation: Astrocytes are the most abundant CNS neuroglia; their "foot processes"
cling to capillaries, controlling the chemical environment of neurons.
3. Which cell type produces the "Myelin Sheath" in the Peripheral Nervous
System (PNS)?
 A) Oligodendrocytes

 B) Schwann cells

 C) Satellite cells

, D) Astrocytes

Explanation: While Oligodendrocytes myelinating the CNS, Schwann cells wrap
around individual axons in the PNS.
4. The part of the neuron that "receives" incoming signals from other neurons is
the:
 A) Axon

 B) Dendrite

 C) Myelin sheath

 D) Axon terminal

Explanation: Dendrites provide a large surface area for receiving signals and convey
them toward the cell body (soma).
5. What is the specific name for the "gaps" in the myelin sheath along an axon?
 A) Synaptic clefts

 B) Nodes of Ranvier

 C) Axon hillocks

 D) Myelin notches

Explanation: Nodes of Ranvier allow for Saltatory Conduction, where the electrical
signal "jumps" from node to node, significantly increasing speed.
6. Which neuroglia are the "macrophages" of the CNS, cleaning up debris and
pathogens?
 A) Microglia

 B) Ependymal cells

 C) Astrocytes

 D) Schwann cells

Explanation: Microglia are small, thorny cells that monitor neuron health and transform
into phagocytes when they detect damage.
7. "Ependymal cells" are specialized for which function?
 A) Myelin production

,  B) Circulating Cerebrospinal Fluid (CSF)

 C) Protecting the cell body

 D) Speeding up action potentials

Explanation: Ependymal cells line the central cavities of the brain and spinal cord; their
cilia help circulate the CSF.
8. Most sensory neurons in the body are structurally classified as:
 A) Multipolar

 B) Bipolar

 C) Unipolar (Pseudounipolar)

 D) Anaxonic

Explanation: Unipolar neurons have a short single process that divides like a "T."
These are common in dorsal root ganglia.
9. The "Axon Hillock" is significant because it is the site where:
 A) Myelin is produced.

 B) The Action Potential is initiated.

 C) Neurotransmitters are stored.

 D) The nucleus is located.

Explanation: Often called the "trigger zone," the axon hillock sums up the incoming
signals to determine if a threshold is reached.
10. Which term describes a "bundle of axons" in the Peripheral Nervous System?
 A) Tract

 B) Nucleus

 C) Nerve

 D) Ganglion

Explanation: In the PNS, a bundle of axons is a Nerve; in the CNS, it is called a Tract.


Part 2: Neurophysiology & Action Potentials