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A mammary gland is an exocrine gland in humans and other mammals that produces milk to feed young offspring.Mammals get their name from the Latin word mamma, "breast".The mammary glands are arranged in organs such as the breasts in primates (for example, humans and chimpanzees), the udder in ruminants (for example, cows, goats, sheep, and deer), and the dugs of other animals (for example, dogs ...
During both of these periods, progesterone levels are high. Because the hormonal profile of a pregnant female and a female in diestrus are the same, sometimes a non-pregnant female will go through a period of pseudopregnancy. At that time she may gain weight, have mammary gland development, produce milk, and exhibit nesting behaviours. 4.
Breast development, also known as mammogenesis, is a complex biological process in primates that takes place throughout a female's life. It occurs across several phases, including prenatal development, puberty, and pregnancy. At menopause, breast development ceases and the breasts atrophy.
The mammary glands of mammals are specialized to produce milk, a liquid used by newborns as their primary source of nutrition. The monotremes branched early from other mammals and do not have the teats seen in most mammals, but they do have mammary glands. The young lick the milk from a mammary patch on the mother's belly.
Branching morphogenesis is also evident in the ductal formation of the mammary gland. [23] [17] Primitive duct formation begins in development, but the branching formation of the duct system begins later in response to estrogen during puberty and is further refined in line with mammary gland development. [17] [24] [25]
The mammary ridge is primordial for the mammary glands on the chest in humans, and is associated with mammary gland and breast development.. In human embryogenesis, the mammary ridge usually appears as a narrow, microscopic ectodermal thickening during the first seven weeks of pregnancy and grows caudally as a narrow, linear ridge. [1]
Lactiferous ducts are ducts that converge and form a branched system connecting the nipple to the lobules of the mammary gland.When lactogenesis occurs, under the influence of hormones, the milk is moved to the nipple by the action of smooth muscle contractions along the ductal system to the tip of the nipple.
The increased secretion of testosterone from the testes during puberty causes the male secondary sexual characteristics to be manifested. [23] Testosterone directly increases size and mass of muscles, vocal cords, and bones, deepening of the voice, and changing the shape of the face and skeleton. [1]