12. The Central Nervous System

A new diet wonder drug is designed to block the release of orexins. How might this cause weight loss? Predict the potential adverse effects that might come from blocking orexin release.

Match the names of the supporting cells found in column B with the appropriate descriptions in column A.

Column A 

_______ (1) myelinates nerve fibers in the CNS 

_______ (2) lines brain cavities 

_______ (3) myelinates nerve fibers in the PNS 

_______ (4) CNS phagocyte

________(5) helps regulate the ionic composition of CNS extracellular fluid

Column B

a. Astrocyte

b. Ependymal cell

c. Microglial cell

d. Oligodendrocyte

e. Satellite cell

f. Schwann cell

a. Contrast unipolar, bipolar, and multipolar neurons structurally.

b. Indicate where each is most likely to be found.

Histological examination of a slice of neural tissue reveals a bundle of nerve fibers held together by cells whose multiple processes wrap around several fibers and form a myelin sheath. The specimen is likely to be:

a. A nucleus

b. A ganglion

c. A nerve

d. A tract

Neuroglia present in large numbers in areas of bacterial infection in the brain are most likely:

a. Oligodendrocytes

b. Astrocytes

c. Ependymal cells

d. Microglia

What is the basis for the functional classification of neurons?

Two major cell groups make up the nervous system—neurons and supporting cells such as astrocytes and Schwann cells. Which are 'nervous' cells?

Why? What are the major functions of the other cell group?

Phagocytic cells in nervous tissue of the CNS are:

(a) Astrocytes

(b) Ependymal cells

(c) Oligodendrocytes

(d) Microglia.

The neural cells responsible for the analysis of sensory inputs and coordination of motor outputs are:

(a) Neuroglia

(b) Interneurons

(c) Sensory neurons

(d) Motor neurons

Why can't most neurons in the CNS be replaced when they are lost to injury or disease?

Describe the stages of sleep and outline the order in which we progress through these stages during a typical night's sleep

Explain how the cerebellum is physically connected to the brain stem.

A professor unexpectedly blew a loud horn in his anatomy and physiology class. The students looked up, startled. The reflexive movements of their eyes were mediated by the:

a. Cerebral cortex

b. Inferior olives

c. Raphe nuclei

d. Superior colliculi

e. Nucleus gracilis

Choose the correct term from the key to respond to the statements describing various brain areas.

Key:

a. Cerebellum

b. Corpora quadrigemina

c. Corpus callosum

d. Striatum

e. Hypothalamus

f. Medulla

g. Midbrain

h. Pons

i. Thalamus 

________ (1) basal nuclei involved in fine control of motor activities  

________ (2) region where there is a crossover of fibers of descending pyramidal tracts  

________ (3) control of temperature, autonomic nervous system reflexes, hunger, and water balance 

________ (4) houses the substantia nigra and cerebral aqueduct 

________ (5) relay stations for visual and auditory stimuli input; found in midbrain 

________ (6) houses vital centers for control of the heart, respiration, and blood pressure 

________ (7) brain area through which all the sensory input is relayed to get to the cerebral cortex 

________ (8) brain area most concerned with equilibrium, body posture, and coordination of motor activity

Colleen falls down a flight of stairs and bumps her head several times. Soon after, she develops a headache and blurred vision. Diagnostic tests at the hospital reveal an epidural hematoma in the temporoparietal area. The hematoma is pressing against the brainstem. What other signs and symptoms might she experience as a result of the injury?