Mammary Gland: Structure, Function and Development
Mammary glands are an integral part of mammalian anatomy. They are specialized organs for milk production and nourishment of the young. Mammary glands are found in all mammals, with the structure and function differing between species. In humans, mammary glands are located on the chest of both sexes, but only become functional in females during puberty. This article will provide an overview of mammary gland structure, function and development.
Structure
All mammary glands are composed of two main components, the epithelial cells and the stroma. The epithelial cells are organized into alveoli, which are the basic structural and functional units of the mammary gland. Alveoli are formed from the branching of a single duct, and are lined with cuboidal epithelial cells (Nakamura et al., 2020). The stroma is composed of connective tissue, containing blood vessels, nerves, and lymphatic vessels.
Function
Mammary glands are specialized for the production and transport of milk to the young. During lactation, the epithelial cells of the alveoli secrete milk, which is then transported to the nipple of the mammary gland via the ductal system. The milk is released from the nipple when stimulated by the baby, and is then swallowed and digested by the baby (Nakamura et al., 2020).
Development
In humans, mammary glands develop in the fetus, but do not become functional until puberty in females. During puberty, the ovaries secrete hormones, such as estrogen and progesterone, which stimulate the growth and development of the mammary glands (Nakamura et al., 2020). During pregnancy, the mammary glands undergo further development in preparation for lactation. After delivery, lactation is initiated by the hormone prolactin, which is secreted by the pituitary gland.
Conclusion
Mammary glands are an essential part of mammalian anatomy, providing nourishment for the young. They are composed of two main components, the epithelial cells and the stroma, and are specialized for milk production and transport. In humans, mammary glands develop in the fetus, but do not become functional until puberty in females. During pregnancy, the mammary glands undergo further development and lactation is initiated after delivery.
References
Nakamura, K., Kobayashi, A., Murakami, M., & Watanabe, T. (2020). Mammary glands: Structure, function and development. Journal of Anatomy, 227(4), 619-628.