The document describes the anatomy and physiology of the breast. It discusses the gross and microscopic structures of the breast, including lobes composed of lobules that contain alveoli and lactiferous ducts. Lactation is controlled by hormones like progesterone, estrogen, and prolactin. During suckling, oxytocin causes myoepithelial cell contraction to eject milk into the lactiferous ducts and out the nipple.