Gray and white matter : composition , location and difference

Grey (British)  gray (American) matter and white matter are  found within the  central nervous system.

Composition of gray matter :

1.      Neuron cell body,

2.      Initial portion of dendrites and axon

3.      Neuroglia

4.      Blood vessels

Composition of white matter:

1.      White matter contain

2.      numerous dendrites and myelinated axons, 

3.      neuroglia, and

4.      blood vessels.

Colour:

Gray matter:  actually has a very light gray colour with yellowish or pinkish hues, which come

from blood vessels and neuronal cell bodies.

White matter:  the colour of white matter arises mainly from the whiteness of myelin.

Location

location of gray matter ::

In cerebrum and cerebrum gray matter situated in outer layer of these organs.

In spinal cord it is situated in inner layer of this organ .

A small collection of gray matter known as nuclei present within the white matter. Example :  basal nuclei/ nuclei: caudate nucleus, putamen, globus pallidus , substantia nigra, subthalamic nucleus , nucleus accumbens and  brain stem nuclei (red nuclei, cranial nerve nuclei) are spread within the cerebral white matter.

Cerebellar nuclei dentate nuclei, fastigi, emboliform etc are the small collection of gray matter present within the white matter of cerebellum .

Ganglia are small collection of gray matter (neuron cell body ) situated outside the central nervous system .

Location of white matter:

White matter forms the bulk of the deep parts of the cerebrum and cerebellum and the superficial parts of the spinal cord  

Difference between gray matter and white matter

Topics	Gray matter	White matter
Composition	Nerve cell body , Neuroglia, Processes , Blood vessels	Neuroglia, Processes , Blood vessels
Colour	Light grey	White
Percentage	Occupy 40% of brain	Occupy 60% of brain
Maturity	Girl  11 years Boy 12 years	Girl 25 years Boy 20 years
Sex difference	Male 6.5 more gray matter	Female   contain 10 times more  white matter
Proportion of	Men have higher proportion of white matter	women have higher proportion of grey  matter
Function	It is the information processing region  of brain	It makes connection between different information processing region of brain
Oxygen use	It uses almost 95% of oxygen	It uses remaining  5%
Loss of volume	It volume losses constantly throughout the life	its volume losses start after mid age
Other name of	Gray matter also known as substantia grisea	White matter also known as substantia alba