The Mammary Glands

The mammary glands are accessory organs of the female reproductive system that are specialized to secrete milk following pregnancy. They are located in the subcutaneous tissue of the front thorax within the elevations which are called breasts. A "nipple" is located near the tip of each breast, and it is surrounded by a circular area of pigmented skin called the "areola." A mammary gland is composed of fifteen to twenty irregularly shaped lobes, each of which includes alveolar glands, and a duct (lactiferous duct) that leads to the nipple and opens to the outside. The lobes are separated by dense connective tissues that support the glands and attach them to the tissues on the underlying pectoral muscles. Other connective tissue, which forms dense strands called "suspensory ligaments," extends inward from the skin of the breast to the pectoral tissue to support the weight of the breast. The breasts are really modified sweat glands, which are made up of fibrous tissues and fat that provide support and contain nerves, blood vessels and lymphatic vessels.