Neurology deals with the structure, function and diseases of the nervous system. The nervous system makes up about 3% of your total body weight. Aside from being one of the smallest body systems it is the most complex. Neurons continuously send nerve impulses to communicate and regulate body tissues. The brain is so powerful that it consumes 20% of the bodies oxygen supply. The nervous system together with the endocrine system plays the key role in maintaining body homeostasis.