100% CORRECT ANSWERS
List and describe the layers of the meninges.
Dura mater
Arachnoid mater
Pia mater
Dura mater:
-Outer periosteal layer
-most superficial of the three spinal meninges
-thick strong layer composed of dense irregular connective tissue
-surrounds spinal cord and is separated from vertebrae by epidural space
Arachnoid mater:
-middle of the meningeal membranes
-thin, avascular covering comprised of cells and thin, loosely arranged collagen
and elastic fibers
-adheres to dura and is separated from pia by fibers spanning the subarachnoid
space that is filled with cerebrospinal fluid (CSF)
Pia mater:
-innermost meninx
-thin transparent connective tissue layer that adheres to the surface of the spinal
cord and brain
-delicate membrane that follows contours of spinal cord
-continues inferiorly as a fibrous terminal filum that fuses with dura to form
coccygeal ligament
,satellite cells function
-Surround somas of neurons in the ganglia
-provide electrical insulation and regulate chemical environment of neurons
microglial cells function
Phagocytize and destroy microorganisms, foreign matter, and dead nervous tissue
Astrocytes function
-Cover brain surface and nonsynaptic regions of neurons
-form supportive framework in CNS
-induce formation of blood-brain barrier
-nourish neurons
-produce growth factors that stimulate neurons
-promote the formation of synapses and neural circuitry
-communicate electrically with neurons and may influence synaptic signaling
-form scar tissue to replace damaged nervous tissue
Schwann cells function
-Form neurilemma around all PNS nerve fibers and myelin around most of them
-aid in regeneration of damaged nerve fibers
ependymal cells function
-Line cavities of brain and spinal cord
-secrete and circulate cerebrospinal fluid
Wernicke area function
-recognition of spoken and written language
-formulates phrases and transmits plan of speech to Broca area
List and describe the functions of the hypothalamus
-major control center of the endocrine and autonomic nervous systems
-plays an essential role in the homeostatic regulation of nearly all organs of the
, body
-Hormone secretion
-Autonomic effects
-Thermoregulation
-Food and water intake
-Sleep and circadian rhythms
-Memory
-Emotional behavior and sexual response
-produces orexins: neuropeptides that stimulate wakefulness
posterior (dorsal) horns of the spinal cord
-Receives sensory input information and also receives input that is involved in the
coordination of reflexes
-receives sensory nerve fibers from the spinal nerves, which usually synapse with
networks of interneurons in the horn
Dopamine
-elevation of mood and control of skeletal muscles
Acetylcholine
-excites skeletal muscle
-inhibits cardiac muscle
-has excitatory or inhibitory effects on smooth muscle and glands depending on
location
-secreted by all preganglionic neurons
Norepinephrine
-involved dreaming, waking, and mood
-excites cardiac muscle
-can excite or inhibit smooth muscle and glands depending on location
Epinephrine