Gray matter consists of the of neurons

Gray matter consists of the unmyelinated axons of neurons.

Explanation:

The outer layer of the brain consists of the grey matter and white matter. The grey matter gets its name by the pinkish grey colour obtained by the greyish colour of the neurons and the red colour from the capillaries.

The grey matter consists of the dentrites, axons and cell bodies and this is essential for memory, attention and learning.  

The unmyelinated axons are not covered by the fat protein myelin and these axons carry signals.They are the ones to help the processing of information in the brain.  

a time line cause it goes from 685 to 978

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