The volume of grey matter peaks at the adolescent age of child, however it starts growing since the childhood. It is considered that a girl’s adolescent age starts from 11 years while a boy’s adolescent age starts from 12 years. Thus, grey matter reaches at its peak when girls reaches the age of 11 years and boy reaches the age of 12 years.
Grey matter starts declining as adulthood is reached in both male and female.
Cell membranes serve as barriers and gatekeepers. They are semi-permeable, which means that some molecules can diffuse across the lipid bilayer but others cannot.
