Organs In The Human Body

The organs in a human body are made of a structure called tissue which is also made of cells with similar functions. Tissues are commonly categorized by the function of the cells that make them up. There are four types of tissues in the human body which are nervous, epithelial, muscular, and connective.

The main components that make up nervous tissue are nerve cells or neurons. An important structure of nervous tissue are the neuroglial cells. Neurons are a specialized type of cell that receive and transmit information as electrical or chemical signals. Neurons pass on the information by synapses which are structures that resemble junctions in non-neural cells (Campbell, 2004).

A neuron consists of three elements. The soma is the central body

Neurons are still an enigma because of the complexity of their functions which can only be achieved by the unique types and shapes of neurons. There could be more than a hundred types of neurons in the CNS alone, some of those unique types of neurons that have already been discovered are the pyramidal neuron, found in the prefrontal cortex, which is named after the key feature of its triangular shape (Elston, 2003). Some other unique types are basket cells, double bouquet cells, spiny neurons, chandelier neurons, and Purkinje cells. Some of those unique types of cells are neurons while others aid in the passing of information similarly to interneurons (Purves, 2008) (Woodruff and Yuste, 2008) (Yarzagaray and Linardakis,

The CNS consists primarily of the brain, spinal cord, and contains tissues other than the nervous tissue such as small amounts of connective tissue and blood vessels (Campbell, Reece and Simon, 2004). There are two types of nervous tissue in the CNS. Grey matter is composed of neurons, synapses, blood vessels, and neuroglial cells. The neurons that constitute grey matter have copious amounts of somata and minute quantities of myelinated axons. Myelin is a fatty substance that envelops axons constructing a sheath that acts as an insulator for the electrical impulses that travel through the axon and appears as a white colour. Grey matter is associated with muscle control, some senses such as sight, and other abilities for instance restraint (Kolb and Whishaw, 1990). The other type of nervous tissue found in the CNS is white matter that is differentiated from gray matter by the relatively fewer cell bodies and the significantly superior amounts of long range myelinated axons. Although grey matter is chiefly correlated to processing and cognition, the regulation of the transmittance of communication between different brain regions is the function of the white matter (Douglas Fields, 2008) (MILLER, ALSTON and CORSELLIS, 1980) (Ransohoff and Benveniste,