3 – Neuro Histology Part I Flashcards
Cell types of CNS:
-neurons
-glia
-microglia
-endothelial
Glia in CNS:
-oligodendrocytes
-astrocytes
-ependyma
*all derived from neural tube (neural SC)
Microglia:
-macrophages recruited to CNS
-from mesoderm
Endothelial cells:
-invading CNS to nourish
*important for making BBB
-from mesoderm
Cell types of PNS:
-sensory and motor neurons
-Schwann cells
-pericytes (support, role in BBB)
Tissues of CNS:
-white matter vs. grey matter
-meninges
White matter:
-myelinated axons
>makes it look white due to fat
-glia
Grey matter:
-cell bodies
-some glia
Meninges:
-cover the entire CNS
-3 layers of connective tissue
>from invading fibroblasts from mesoderm
-not in PNS
3 layers of meninges: outside to inside
-dura mater: tough
-arachnoid mater: web-like structure
-pia mater: adhered to brain tissue
Neurons:
-functional units of NS
>form synapses with other cells (neurons or target organs)
-lots of them! (billions)
>more in sophisticated animals (ex. humans)
-supported by glia
*way more glia then neurons
Neurons structure:
-cell body (soma)
-dendrites (where neurons synapse)
-axon
-terminal branches
-telodendrites (synapse with next neuron)
*unidirectional signalling
Function of neurons:
-signal transmission from PNS to CNS to allow animal to respond to environmental changes
Neurons in CNS:
-responsible to integrating and interpreting
Neurons in PNS:
-responsible to detection and performing response