C . Biological and Physical Changes The period of adolescence is marked by certain universal physical and biological changes in the body which take place in particular sequences. These changes lead to the attainment of sexual maturity. The time when sexual maturity is reached is called puberty .
Menarche (first menstruation) is usually considered the point of sexual maturity for girls. There is no corresponding definite event marking puberty for boys, although a criterion sometimes used is the production of spermatozoa. Puberty occurs at different average ages in different cultures. A criterion of puberty that has been found useful for both boys and girls is that of maximum yearly increase in height.
The age of most rapid growth comes just before menarche for girls and before certain adult characteristics in boys. This period during which physical and biological changes occur, leading to puberty is called pubescence . For most girls this period ranges from years to years, and for boys it is years to years. Following is the list of changes in girls and boys showing normal sequence for development during pubescence.
Girls Boys Initial enlargement of breasts Beginning growth of testes Straight, pigmented pubic hair Straight, pigmented pubic hair Kinky pubic hair Early voice changes Age of maximum growth First ejaculation of semen Menarche Kinky pubic hair Growth of axillary hair Age of maximum growth Growth of axillary hair Marked voice changes Development of the beard While the physical changes that take place in the body with the onset of puberty are universal, the psychological and social impact of these changes on the person vary from culture to culture and within a culture from person to person. We will discuss these aspects under the next two headings – socio-cultural contexts and emotional changes.