PHYSIOLOGY EXAM GUIDE 2024/2025.
COMPLETE QUESTIONS AND ANSWERS
1 . Nervous System: - One of the two systems for communication in the
body (endocrine system is the other)
- Allows the trillions of cells in the body to effectively work together
to maintain homeostasis and function)
- 2 major anatomical divisions: central nervous system and
peripheral nervous system
- Only 1 nervous system in the body but multiple divisions are
only for convenience to understand function
2. Neuroscience: Study of the nervous system and includes
neuroanatomy and neurophysiology
3. Neurology: Branch of medicine that deals with diagnosis and
treatment of neurological disorders
4. Central Nervous System (CNS): Consists of the brain and
spinal cord 5. Peripheral Nervous System (PNS): - Consists of
everything except CNS
- Functionally divided into sensory division & motor division
6. Sensory Divison: - Carries signals by way of afferent nerve fibers
from receptors to the CNS
- Has 2 subdivisions: Visceral sensory division & Somatic sensory
division
7. Motor Division: - Carries signals by way of efferent nerve fibers
from CNS to the effectors (mainly muscles and glands)
- Motor division has 2 subdivisions: visceral motor division
(autonomic nervous system) & somatic nervous system
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, MCDB (NERVOUS SYSTEM) ANATOMY &
PHYSIOLOGY EXAM GUIDE 2024/2025.
COMPLETE QUESTIONS AND ANSWERS
8. Autonomic Nervous System: Has 2 further divisions: Sympathetic
& Parasympathetic divisions
9. Sympathetic Division: Tends to arouse the body for action
(increase pulse rate, increase breathing, but inhibits digestion)
10. Parasympathetic Division: Calming effect (rest and digest)
1 1 . Neurons (Nerve Cells): - 3 functional properties: Excitability,
conductivity, and secretion - 3 classes of neurons: sensory (afferent),
interneurons (association), & motor (efferent) 12. Sensory Neurons:
Specialized to detect stimuli (light, heat, pressure, chemicals, etc)
13. Interneurons: Lie entirely in CNS and receive signals to process,
store and retrieve information (about (90% of body's neurons &
interneurons)
14. Motor Neurons: Send signals to mainly muscles and glands to
carry out body's responses
15. Structural Classes of Neurons: Unipolar, Bipolar, Multipolar and
Anaxonic neurons
16. Myelin Sheath: - Similar to the rubber insulation on a wire that
protects the axon but causes faster signals to be sent and is more energy
efficient
- Composition is like that of the plasma membrane (about 20%
protein and 80% lipid, mainly phospholipids, glycolipids, and
cholesterol) - Myelin is the difference between white and gray
matter
- Speed of conduction depends on the presence or absence of the
myelin sheath and diameter of the nerve fiber (slow .5 - 2 m/sec. fast
120 m/sec)
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, MCDB (NERVOUS SYSTEM) ANATOMY &
PHYSIOLOGY EXAM GUIDE 2024/2025.
COMPLETE QUESTIONS AND ANSWERS
17. Diseases of the Myelin Sheath: Multiple sclerosis and tay-
sachs disease
18. Nodes of Ranvier: Gaps between the segments of myelin
19. Multiple Sclerosis: - Oligodendrocytes and the myelin sheaths of
the CNS deteriorate and are replaced by scar tissue
- Typically diagnosed between 20 and 40 years of age
- Nerve conduction is disrupted
- Symptoms depend on location of the disruption: double vision,
blindness, speech defects, neurosis, tremors, numbness - Most die
7 to 32 years after diagnosis
- Cause is uncertain, but speculation linked to an immune response
triggered by a virus in genetically susceptible individuals - No cure
20. Tay-Sachs Disease: - Genetic disorder predominately in Eastern
European Jewish ancestry
- Abnormal accumulation of a glycolipid called GM2 in the myelin
sheath
- Disrupts conduction of the nerve signals
- Signs usually begin before the child is one year old
- Most die by the age of 3-4 years
- Symptoms: blindness, loss of coordination, and dementia
21 . Current: Is flow of charged particles from one point to another
22. Depolarization: Membrane voltage shifts to a less negative
value
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