4. The Brain The brain is the primary organ of the central nervous system contained within the skull. It receives and interprets the countless signals that are sent to it from other parts of the body and from the external environment. The brain makes us conscious , emotional and intelligent. It is the control center for movement, sleep, hunger, thirst, and every vital activity necessary to survival. The brain controls all human emotions like love, hate, fear, anger, elation, and sadness.
5. The adult human brain is a 1.3 âkg (3-lb) mass of pinkish-gray jellylike tissue made up of approximately 100 billion nerve cells or neurons. The brain is divided into three parts: the cerebrum, the cerebellum, and the brain stem. Different areas of the brain control specific activities.
6. Cerebrum or the forebrain is the largest part of the brain. It is responsible for the higher thought processes such as memory, judgment, and reason. Cerebrum
11. Cerebellum The cerebellum is at the back of the brain stem and is linked to it by nerve tracts. It receives information from muscle tendons and the balance organ in the inner ear. It is concerned with the maintenance of posture and balance , and the coordination of movements.
13. Spinal Cord It is a cylinder of nerve tissue as thick as finger and about 45 cm long. Coming out of the spinal cord on both sides and at regular intervals are the spinal nerve roots. The spinal nerves branch out to reach different parts of the body.
14. Neuron It is the basic unit of structure and function of the nervous system