Brain and Spinal Cord

See the following table for comparison

location of -----------------Brain ----------------------------------- Spinal cord
White matter--------------- inside ------------------------------------outside
Grey matter --------------- outside---------------------------------- inside
Nerve cells------------------more--------------------------------------less
receptors sites--------------Yes--------------------------------------No
Nerve numbers-------------only 12 pairs of nerves------------has 31 pairs

Receptors site for neurotransmitter to act on them so that nerve impulse or action potential can be formed if threshold value is greater.


Brain nerves such as optic(I), olfactory(II), occulomotor(III),vagus(X)and glosspharyngeal (IX)
if you want more information, visit the following website
http://spot.pcc.edu/~cpierpoi/231/cnerv.doc

The spinal cord is a thin, tubular structure that is an extension of the central nervous system from the brain and is enclosed in and protected by the bony vertebral column. The main function of the spinal cord is transmission of neural inputs from the periphery to the brain and vice versa and is a vital structure in our survival and functional capacity.

In animals, the brain, or encephalon (Greek for "in the head"), is the control center of the central nervous system. In most animals, the brain is located in the head, protected by the skull and close to the primary sensory apparatus of vision, hearing, taste and olfaction. In humans, it is an organ of thought. While all vertebrates have a brain, invertebrates have either a centralized brain or collections of individual ganglia. Brains can be extremely complex. For example, the human brain contains more than 100 billion neurons, each linked to as many as 10,000 others.