The mammary gland is a highly evolved and specialized organ present in pairs, one on each side of the anterior chest wall. It is present in both sexes, but it is well developed in females and rudimentary in males. The mammary gland is a modified sweat gland made up of the parenchyma and is an apocrine type of gland. The primary function of the mammary gland is to secrete milk. During pregnancy, the hormones progesterone and prolactin are released, and the progesterone interferes with prolactin, preventing the mammary glands from lactating. During this time, small amounts of a pre-milk substance called colostrum are produced. After childbirth, progesterone levels decrease, and the levels of prolactin remain raised, signaling the mammary glands to begin lactating.
Here are some key features of the mammary gland:
- Location: The mammary gland is situated in the pectoral region in the superficial fascia. However, a part of it called the axillary tail pierces the deep fascia and lies in the axilla.
- Shape: The shape of the mammary gland is hemispherical in young adult females but becomes pendulous in the later stage of life.
- Weight: Though it varies from one person to another, the mammary gland usually weighs between 500 to 1000 grams each.
- Development: Mammary glands only produce milk after childbirth. During pregnancy, the hormones progesterone and prolactin are released. The progesterone interferes with prolactin, preventing the mammary glands from lactating. During this time, small amounts of a pre-milk substance called colostrum are produced. After childbirth, progesterone levels decrease, and the levels of prolactin remain raised, signaling the mammary glands to begin lactating.
In summary, the mammary gland is a gland located in the breasts of females that is responsible for lactation, or the production of milk. It is a modified sweat gland made up of the parenchyma and is present in both sexes, but it is well developed in females and rudimentary in males.
