Adolescence begins as the pituitary gland secretes hormones
which spur the final growth spurt and also stimulate the sex glands to secrete
sex hormones .. In a girl, the ovaries enlarge and there are such physical
changes as breast enlargement and pubic hair, most of them begun by the
thirteenth year.
When the ovaries begin to release egg cells, the menstrual
cycle begins. In a boy, between 13 and 16, pubic and underarm hair appears and
the voice begins to deepen as the larynx enlarges. Between 16 and 18 facial
hair appears. Usually between 12 and 13, the testes, scrotum, and penis enlarge
and sperm cell production begins. Girls generally reach their peak height at
about 12. At 13, boys are about 61 inches and girls about 62.
Between 13 and
the end of growth, boys add about 10 or 11 inches. A girl's growth slows after
13, and between 13 and 17 she usually adds about 4 inches. At 13, boys weigh
about 93 pounds and girls 99. Between 13 and 17, boys gain about 50 pounds and
girls about 35. In the teen-age years, fatigue is common; both sexes are prone
to acne as hormone production increases and the skin is affected. Between 17
and 20, the wisdom teeth, the last permanent teeth, appear. Teen-agers
sometimes appear clumsy, it is because they are still adjusting to their
growing bodies.
Muscle strength and endurance in- crease greatly in boys during
adolescence. Because of their growth and vigorous activity, adolescents,
particularly boys, have greater nutritional needs. Girls may require 2,600
calories daily, boys 3,200.
YOUR CHILD
We want to make it very clear that we have been talking in
terms of "the average child." Really, this is a mythical child, a
statistical child, not anyone real child. Your child is an individual and it
would be remarkable if he or she happened to be average in every detail. More
likely, your child will be above average in some respects, below in others, and
may even alternate between the two at various periods.
GROWTH
You might like, and
we think it a good idea, to keep a run- ning record of the weight and height of
your child and the arrival of teeth so your doctor will know whether the rate
of development is within normal limits. Leave that up to him and don't worry
about it yourself. Your child should never be made to feel uncomfortable about
his or her physical development.