Summary

Neural system coordinates and integrates the functions of all organs and responds to changes in the internal and external environments. Neural system includes two types of cells neurons and neuroglia. Neuron forms the structural and functional unit of the neural system. CNS includes brain and spinal cord.

The major parts of the brain are the cerebrum, diencephalon, cerebellum and the brain stem. The brain is protected by the cranium and meninges. CSF provides mechanical protection and nutrients to the CNS. The spinal cord is the continuation of the medulla oblongata and ends at the second lumbar vertebra as conus medullaris.

The components involved in reflex action are called reflex arc. There are pairs of cranial nerves which arise from the brain and pairs of spinal nerves from the spinal cord make the PNS. The PNS is further divided into