Development of the human body used to approximately judge a child's age based on physical development. Puberty is the process of physical changes through which a child's body matures into an adult body capable of sexual reproduction. It is initiated by hormonal signals from the brain to the gonads: the ovaries in a girl, the testes in a boy. In response to the signals, the gonads produce hormones that stimulate libido and the growth, function, and transformation of the brain, bones, muscle, blood, skin, hair, breasts, and sex organs. Physical growth—height and weight—accelerates in the first half of puberty and is completed when an adult
101 Things Removed from the Human Body from their body survived. This program also aired in the USA on the Discovery network's "The Learning Channel" in October 2007. The program contains stories, including a man having a uterus and a man with a teratoma, a type of large tumor. The large jaw tumor segment featured the work Mercy Ships, who have operated floating hospital ships in impoverished areas around the world. 101 Things Removed from the Human Body 101 Things Removed from the Human Body and 101 More Things Removed from the Human Body is a British "shockumentary" series directed by Eric Schotz, which is narrated by