Chapter 2 • Central NervousSystem
ChapterSummary
•The neural tube forms 3 primary vesicles at its cranial end:
-Forebrain (prosencephalon)
-Midbrain
-Hindbrain (rhombencephalon)
•These primary vesicles then develop into 5 secondary vesicles that form the adult derivatives of the CNS.
-The telencephalon forms the cerebral hemispheres
-The diencephalon forms 4 thalamic derivatives
-The mesencephalon forms the midbrain
-The metencephalon forms the pons and cerebellum
-The myelencephalon forms the medulla
•The remainder of the neural tube forms the spinal cord. The lumen of the neural tube will develop into the ventricular system.
•The typical neuron is the multipolar neuron. It consists of a cell body (soma), multiple dendrites, and a single axon. Axons utilize anterograde and retrograde axonal transport to move subcellular elements to and from the soma. Skeletal motor neurons, preganglionic autonomic neurons, and glial cells develop from the neural tube. Glial cells include astrocytes, oligodendrocytes, microglia, and ependymal cells.
