The breast (mamma) is the human mammary gland. In women it is a secondary sex characteristic, that develops morphologically and functionally during puberty under the influence of hormones (thelarche).
In men, the mammary glands show the same basic structure, but remain undeveloped due to the lack of hormonal factors and stay rudimentary.Author: Patrick Lynch, original file here. This file is licensed under the Creative Commons Attribution 2.5 License.
