Maturation is often defined as the course of becoming mature, or advances towards the mature biological state which varies with the biological system considered, whether endocrine, reproductive, skeletal, digestive or immunological. These variations may be designated to eifferences in the timing and tempo of maturation. Timing refers to when a specific maturational event occurs, e.g. age at appearance of pubic hair in boys and girls or age at maximum growth during adolescent growth spurt, while tempo refers to the rate at which maturation progresses. Maturation of the nervous and endocrine systems is a major factor in sexual, skeletal and somatic maturation during late childhood and adolescence.
Individuals end up as adults with an entirely ossified skeleton, ‘but they reach this juncture at different times and attain different adult heights. This offers fundamental difference between growth and maturation. Growth focuses on size attained at a given point in time, whereas maturation focuses on the progress rate in attaining adult size and maturity. However, both processes must be viewed as dynamic cellular processes targeting at the achievement of mature adult state from conception state.