Page 181 - Meeting with Children Book

P a ge | 179

Physical/Sensory Motor

Development

Physical development of the adolescent
is marked by puberty which marks the
end of childhood and the beginning of
sexual maturity. Hormones are

responsible for the development of both primary sex
characteristics related to reproduction (penis in boys and
uterus in females) and secondary sex characteristics (pubic
hair in both genders, breast and hip growth for females, and
voice change for males). Puberty lasts approximately six to
seven years but each young person will have a different on-
set and a different rate of growth. The onset of puberty
typically occurs at age 10 or 11 for females and at age 11 or
12 for males; females usually complete puberty by ages 15
to 17, while males usually finish around ages 16 to 18. By
the completion of puberty, females tend to attain their
individual height, weight, body composition, sex
characteristics, and circulatory and respiratory systems.
These changes are largely influenced by hormonal activity.

The pituitary gland is responsible for hormonal changes
throughout the body in addition to the adrenal, endocrine
and sexual glands. Around the age of 12 or 13, most girls
today begin menstruating. The onset of menstruation is
termed menarche. At this time, females can become
pregnant. Increasing levels of the hormone testosterone
trigger the onset of puberty in boys around ages 12 to 14.
Boys become taller, heavier, and stronger; their voices