Chapter Five: Brain, Motor skills, and Physical Development (Continued)
Growth is the increase in size of the body or its organs and development refers to
changes in size and to the orderly patterns such as growth spurts and more
complicated levels of functioning.
Norms are quantitative measures that provide typical values and variations in
height and weight for children.
Length and Height:
The most rapid increase in body length occurs during the fourth month of
The onset of rapid adolescent growth typically occurs between 10-14 for
girls and 12-16 for boys
The maximum rate of increase in weight takes place shortly after birth.
Newborns, after birth, lose all of their excess body fat and fluids but then
make rapid gains. They double their birth weight in about five months and
triple it by their first birthday
Body growth generally follows a pattern of proximodistal development in which
organs and systems of the body near the middle tend to develop earlier than
those near the periphery.
Infants tend to gain control of their arms and legs sooner than more distant
areas, fingers and toes.
Biological determinants of Body Growth and Development:
Genes do not control growth directly, they regulate physical development
by means of neural and hormonal activity in different organs and body
A person’s height may be closely related to that of his mother and father of
their cultural group
Catch-up growth is an increase in growth rate, that occurs after an illness
or malnutrition is duration and severity are limited and do not occur at
some critical time
Lagging-down growth is a decrease in growth rate after certain factors
have accelerated the expected normal growth rate
Researchers believe that there is some so-called “growth center” in the
brain called the hypothalamus which is a small region of the brain that
orchestrates the genetic instructions for growth.
Hormones are chemicals produced by various glands and secreted directly
into the bloodstream. They circulate to influence cells in other locations of the body to furnish other key mechanisms for converting genetic
instructions into physical development.
Human growth hormones have been distributed to a number of children
Nutrition and Psychological Factors Associated with Physical Development:
Nutrition and Health,
Marasmus is when children fail to grow because they lack sufficient
calories – loss in weight, wrinkly skin, shrunken abdomen
Kwashiorkor is the failure to develop because the diet either contains an
inadequate behavior balance of protein or includes potentially harmful
toxins – lethargic behavior, wrinkled skin, wispy reddish-orange hair,
swelling of the stomach
Deficiencies in vitamins A, B complex, K and calcium are all linked to
growth disorders especially iron-deficiency anemia