Adolescents experience a broad range of developmental stages that occur at various times, depending on the individual. Females, perhaps more than males, experience a broader ranger of physical development during the adolescent period, due to the onset of menstration. Puberty, for all teenagers, is considered a trying time. The physical, cognitive, and emotional development of puberty affects not only the adolescent, but also those around them.
The onset of female puberty is most often noticed through the physical changes of the female body. This period of development usually occurs between the ages of 9 and 11. Bone growth, increases in body fat, breast development, and pubic hair/underarm hair growth are the prominent indicators of puberty's onset. Increases in body fat can be directly related to the onset of menarche, the first menstrual period. It is an important factor for adolescent girls to remember that there are wide variations in the onset and progression of puberty. The onset of male puberty is most noticeable by the physical changes of the male body. The hormone testosterone plays a key role in the development of external genitals, increases in height, and voice changes. Three of the most noticeable changes in boys are penis size, body hair growth, and voice change. .
One psychological aspect of physical change in puberty is certain: Adolescents are preoccupied with their bodies and develop individual images of what their bodies are like. Adolescent girls are more likely than boys to have a negative body image, due to the increase in body fat percentage. Boys, on the other hand, generate a more positive body image, due to the increase in muscle tissue. Santrock, 83. An emotional turmoil for most girls is the desire to be thin.something that becomes more important as their body fat increases. This can lead them to certain damaging behaviors, such as anorexia nervosa or bulimia.