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BreastThe term breast, also known by the Latin mamma in anatomy, refers to the upper ventral region of an animal's torso, particularly that of mammals, including human beings. In addition, the breasts are parts of a female mammal's body which contain the organs that secrete milk used to feed infants. This article focuses on human female breasts, but it should be noted that male humans also have breasts (although usually less prominent) that are structurally identical and homologous to the female, as they develop embryologically from the same tissues. While the mammary glands that produce milk are present in the male, they normally remain undeveloped. In some situations male breast development does occur, a condition called gynecomastia. Milk production can also occur in both men and women as an adverse effect of some medicinal drugs (such as some antipsychotic medication), extreme physical stress or in endocrine disorders. The breasts are covered by skin; each breast has one nipple surrounded by the areola. The areola is colored from pink to dark brown, hairless, and has several sebaceous glands. The larger mammary glands within the breast produce the milk; they consist of several lobules, and each breast has some 10-20 lactiferous ducts that drain milk from the lobules to the nipple, where each duct has its own opening, Most of the breast is connective tissue, i.e., adipose tissue (fat) and Cooper's ligaments. The breasts sit over the pectoralis major muscle and usually extend from the level of the 2nd rib to the level of the 6th rib anteriorly. The superior lateral quadrant of the breast extends diagonally upwards in an 'axillary tail'. A thin layer of mammary tissue extends from the clavicle above to the seventh or eighth ribs below and from the midline to the edge of the latissimus dorsi posteriorly. The arterial blood supply to the breasts is derived from the internal thoracic artery (previously referred to as the internal mammary artery), lateral thoracic artery, thoracoacromial artery, and posterior intercostal arteries. The venous drainage of the breast is mainly to the axillary vein, but there is some drainage to the internal thoracic vein and the intercostal veins. The breast is innervated by the anterior and lateral cutaneous branches of the 4th through 6th intercostal nerves. The nipple is supplied by the T4 dermatome. Both sexes have a large concentration of blood vessels and nerves in their nipples. About 75% of lymph from the breast travels to the ipsilateral axillary lymph nodes. The rest travels to parasternal nodes, to the other breast, or abdominal lymph nodes. The axillary nodes include the pectoral, subscapular, and humeral groups of lymph nodes. These drain to the central axillary lymph nodes, then to the apical axillary lymph nodes. The lymphatic drainage of the breasts is particularly relevant to oncology, since cancer cells can break away from a tumour (breast cancer being a common cancer), and spread to other parts of the body through the lymph system by a process known as metastasis. Check out the following recipes that are tagged "Breast":
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