PSYC 211 Chapter Notes - Chapter 15: Microglia, Meningitis, Medulloblastoma
Document Summary
= a mass of cells whose growth is uncontrolled and that serves no useful function. Malignant = cancerous; not encapsulated, no distinct border btw it and surrounding tissue. Benign = non-cancerous; encapsulated, distinct border, can be cut out, won"t metastasize. Metastasis: process by which cells break off a tumor, travel through vascular system, +grow. Tumors do not arise from nerve cells, which do not divide; they arise from other cells found in brain or from metastases originating elsewhere in the body. Most serious types are metastases and gliomas derived from forms of glial cells. Gliomas glioblastoma multiformae (poorly differentiated glial cells) astrocytoma (astrocytes) ependymoma (ependymal cells that line ventricles) medulloblastoma (cells in roof of 4 oligodendrocytoma (oligodendrocytes) th ventricle) Meningioma cells of the meninges (encapsulated and benign) Pituitary adenoma hormone-secreting cells of pituitary gland. Neurinoma schwann cells or cells of connective tissue covering cranial nerves. Metastatic carcinoma depends on nature of primary tumor.