What marks the beginning of adolescence physically in both males and females?

The onset of puberty is a critical transitional phase that marks the beginning of adolescence in both males and females. Puberty encompasses a series of biological changes that lead to sexual maturity and various physical transformations resulting from hormonal changes. In males, this includes the development of facial hair, deepened voice, and increased muscle mass. In females, it brings about breast development, the start of menstruation, and widening of hips.

While menstruation specifically signifies the onset of reproductive capability in females, puberty is the broader term that includes a whole range of physical changes in both genders. Growth spurts occur during puberty, indicating rapid physical growth, but they are just one aspect of the overall process. Skeletal maturity, on the other hand, happens later in adolescence when the bones fully develop and stop growing, which is also a part of the larger journey of physical development during this time. Thus, puberty is the correct term as it encompasses the entire transformation process marking the onset of adolescence.