"Eeew! What is that vile stench??? Is that you... BABY BOB?"
Puberty is the maturation of different tissues of different organs, which cause both physical and mental changes to the body. The onset of puberty is triggered by the hypothalamus when it sends the pituitary gland a signal to release growth hormones and occurs between 10 and 16 years of age.
Precocious Puberty is a condition in which the changes in the body associated with puberty begin earlier than the normal age of 10 for girls and 12 for boys. These changes in the body include pubic or underarm hair development, rapid height growth - a growth "spurt", acne, “mature” body odor, breast development and menstruation for girls; and voice deepening and enlargement of testicles or penis for boys. Similarly, some girls and boys may experience early growth of pubic and/or underarm hair that isn't associated with other changes in sexual development.
The sebaceous and apocrine glands only start to work in puberty. Due to the fact that when bacteria feeds on the solution of fluids produced by the sebaceous glands and apocrine glands, armpit odor doesn’t occur until the stage of puberty.
All the changes that occur in the body during puberty are the work of hormones. These hormones are produced by the pituitary gland. In male, ICSH (Interstitial CellStimulating Hormone) acts on the male testes to produce the male sex hormone called testosterone. These hormones achieve the psychological and physical changes in boys.
In female, the LH (Lueinising Hormone) and FSH (Follicle Stimulating Hormone), which are known as gonadotrophic hormones act on the ovaries so the ovaries can create the female sex hormones called estrogen and progesterone. These hormones accomplish the psychological and physical changes in females.
(ref.2,7,8, human development)
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