7R: Nerve Cells Flashcards
Two components of the nervous system
CNS: Cerebral cortex, cerebellum, brain stem and spinal cord
PNS: Nerves extending from the spinal cord and dorsal root ganglion
define:
a. gyrus
b. sulcus
a. “humps” in the external part of the brain
b. “valleys” in the external part of the brain
- especially deep sulci are called fissures
What do each control?
a. Frontal lobe
b. Temporal lobe
c. Parietal lobe
d. Occipital lobe
a. primary motor cortex (precentral gyrus)
b. auditory information
c. primary somatosensory cortex (postcentral gyrus)
d. visual information
sections of the CNS
cerebral cortex
brain stem (diencephalon, midbrain, pons, and medulla)
cerebellum
spinal cord
6 layers of the cerebral cortex
I. molecular layer - little cells in this layer
II. external granular layer
III. external pyramidal layer
IV. granular layer
V. ganglionic layer (internal pyramidal cells)(major sensory relay from the periphery)
VI. multiform (polymorphic) layer
Functions of the cerebellum
- coordinates voluntary movements and maintains posture
Layers of the cerebellum
- Molecular layer: not a lot of neurons
- Purkinje layer: purkinje cells = only output cells in the cerebellum. used to use silver stain, now we use immunohistochemistry to view
- Granular layer: many small neurons
what type of neurons are located in the ventral horn?
motor neurons - use a nissl stain to view them
where are grey and white matter located in the brain and spinal cord?
brain: grey matter outside, white matter inside
spinal cord: white matter outside, grey matter inside
Amount of nerve projections on the vertebrae
cervical: 8 Thoracic: 12 lumbar: 5 sacral: 5 coccygeal: 1
ALS (amyotrophic lateral sclerosis)
- loss of motor neurons
- can think, remember etc. just like normal, just can’t move like normal
a. pyramidal interneuron
b. motor neuron
c. sensory neuron
a. CNS
b. spinal cord
c. dorsal root ganglion (pseudounipolar cells)
Glia Cells
a. Astrocytes: induce the endothelial cells to form the BBB
b. Microglia: Macrophages of the CNS
c. Oligodendrocytes: Make myelin in the CNS
d. Ependymal cells: line the CSF area in the CNS
Types of astrocytes and function
function to: support, insulate, electrolyte balance, pH balance of extracellular milieu, sequestration of neurotransmitters, communicate with capillary endothelial cells, interactions with immune system, phagocytosis of extracellular debris, induce the BBB Protoplasmic: prominent in grey matter. they have wavy, thin, fuffy processes Fibrous: prominent in white matter. they have fine, long straight processes
3 types of meninges
P: pia mater: connective tissue layer directly on top of the brain and spinal cord
A: arachnoid: connective tissue and elongated fibroblasts. the subarachnoid space is where cerebrospinal fluid runs
D: dura mater: dense connective tissue.
