breast
Breast (English: breast, latin: mamma) is located in the breast or abdomen of mammals, appearing in pairs. Female breasts include mammary glands and other glands that secrete milk to nurture children. In the embryonic male and female have the same breast tissue structure, but puberty, the female body of hormones, especially estrogen will stimulate the breast development, so that fat accumulation in the chest. And male male hormones will prevent breast development, so adult women's breasts are much larger than men, the development of the breast is the second sexual characteristics of women. Estrogen, luteinizing hormone and prolactin regulate the shape of the breast, so the breast will change with the menstrual cycle. During pregnancy, hormones will cause breast enlargement, ready to secrete milk. Breasts include 15 to 20 milky leaves. The subcutaneous adipose tissue in the milk makes the breasts have its quality and shape. Milk leaves consist of many mammalian lobules, which secrete milk according to the hormone signal. ...