51. Chronological Devt of secondary characteristics Age Boys GIrls 9-11 Prepubertal weight gain Breasts: elevation of papilla with breast bud formation, areolar diameter enlarges 11-12 Sparse growth of straight, downy slightly pigmented hair at base of penis Scrotum become textured Growth of penis and testes Perspiration increases Straight hair along the labia, vaginal epithelium cornified Perspiration also increases 12-13 Pubic hair present across pubis Penis lengthens Dramatic linear growth spurt Breast enlargement occurs Pubic hair grows darker; spreads all over pubis Breast enlarges, still no protrusion of nipples axillary hair is present Menarche occurs
71. SECONDARY SEX CHARACTERISTICS Age Males Females 13-15 Growth spurt coninues Pubic hair is abundant and curly Testis, scrotum and penis enlarging further Facial hair, voice changes Pubic hair is thick and curly- triangular Menstruation is ovulatory Pregnancy is possible 15-16 Genitalia adult Scrotum dark and heavily rugated Facial and body hair is present Sperm production is mature Pubic hair abindant Areolas no longer project as separates ridges from the breast Facial acne 16-17 Pubic hair curly and abundant may extend to the medial aspect of the thigh Facial acne Gynecomastia – enlarged breast tissue End of skeletal growth 17-18 End of skeletal organ
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Editor's Notes
The term knock knee describes a large distance between the ankles when the knees are touching.
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