Adolescence is the period of reproductive maturity which lies usually between the ages of 10 to 18 years . During adolescence a child's boy undergoes many changes physically as well as mentally . Voice of boys become harsh as chords of voice box get loosened and thickened during adolescence . Height gain in children stops after adolescence . The onset of puberty or development of secondary sexual characters and maturity of reproductive parts are controlled by hormones that become functional at the onset of adolescence . Hormones are the secretions of endocrine glands which secretes them directly into the bloodstream . Pituitary glands secrete hormones and other stimulating hormones that make other glands such as the testes , ovary , adrenals etc.,secrete hormones . Testosterone is the male hormone and estrogen is the female hormone that bring about development of several secondary sexual characters . The uterine wall in female prepares itself to receive the developing fertilized eggs . In case there is no fertilization , the thickened lining of the uterine wall breaks down and goes out of the body along with the blood . This is called menstruation . It is important to take balanced diet for over all growth and development during adolescence .