Chapter 32, Problem 11SQ

Summary Introduction

Introduction:

Neurons are the brain cells that are specialized to transmit nerve impulses. Most of the vertebrate axons have a myelin sheath, a discontinuous covering composed of myelin-producing glial cells that wrap around the axon one after another. In the peripheral nervous system, myelin sheaths are formed by glial cells called Schwann cells. Astrocytes are star shaped glial cell present in the brain that play an important role in the blood-brain barrier, immune defense, and synthesize nerve growth factor. Microglia is a type of neuroglia which is found in the brain and spinal cord and play role of immune defense in the central nervous system.