NERVOUS TISSUE
The nervous tissue in general develops from the ectoderm of the embryo, but the microgliocytes.
It does not have a matrix.
The special properties of the cells of the nervous tissue are, excitability and conductivity. The response may be sensation, such as pain or some activity such as muscle contraction or glandular secretion.
The cells are surrounded by special connective tissue, neuroglia in CNS & schwann cells in PNS.
COMPONENTS OF NERVOUS TISSUE -
Neuron is a structural and functional unit of the nervous tissue. Neurons are the longest cells in the body.
Human nervous system has about 100 billion neurons. Majority of the neurons occur in the brain.
Fully formed neurons never divide and remain in interphase throughout life. Certain neurons have flask shaped cytons and are called Purkinje cells, which occur in the cerebellum of the brain.
A neuron consists of main cell body and cytoplasmic processes arising from it.