The breast is the upper ventral region of an animal’s torso, particularly that of mammals, including human beings. The breasts of a female primate’s body contain the mammary glands, which secrete milk used to feed infants.
Male breasts and female breasts in human beings develop from the same embryological tissues. In females at puberty sex hormones, mainly estrogens, promote breast development. In males this generally does not happen. As a result, breasts become more prominent in adult females than in males..
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