Nerve Tissue and Nerve cells in Animals

•Nervous systhem is composed of various cells having different function.
•Neuron is basic cell type.
•Other cells are; astrocyte, microglial cells, oligodendrocytes, shwann cells, ependimal cells

•Neurons have two extension: long one is called as axon, short one dentrites.
•Neurons can be classified acording to type of extension: Unipolar, bipolar, Multipolar.
•The majority of invertebrates interneurons and motorneurons are unipolar.


•Astrocytes provide connection between capillaries and neurons.
•Oligodendrocyte make myelin sheeth
•Microglia are phagocytic, motile cells that engulf and destroy cellular debris and microbes.

•Glial Cells are three type: Astrocyte, oligodentrocyte, microglia.


•In the peripheral nervous system, myelin is formed by Schwann cells.
•Each Schwann cell associates with only one axon, when forming a myelinated internode.