New! Sign up for our free email newsletter.
Reference Terms
from Wikipedia, the free encyclopedia

Mammary gland

Mammary glands are the organs that, in the female mammal, produce milk for the sustenance of the young. These exocrine glands are enlarged and modified sweat glands and are the characteristic of mammals which gave the class its name.

The basic components of the mammary gland are the alveoli (hollow cavities, a few millimetres large) lined with milk-secreting cuboidal cells and surrounded by myoepithelial cells. These alveoli join up to form groups known as lobules, and each lobule has a lactiferous duct that drains into openings in the nipple. The myoepithelial cells can contract, similar to muscle cells, and thereby push the milk from the alveoli through the lactiferous ducts toward the nipple, where it collects in widenings (sinuses) of the ducts. As the infant begins to suckle, the hormonally mediated "let down reflex" ensues and the mother's milk is secreted into - not sucked from the gland by - the baby's mouth.

Related Stories
 


Health & Medicine News

November 13, 2026

A new study reveals that viral infections may leave behind hidden damage to the immune system long after symptoms disappear. Researchers found that mice recovering from an acute infection experienced ...
A study of more than 750,000 pregnancies found that early exposure to Ozempic, Wegovy, and similar drugs was not linked to increased pregnancy complications when used for weight loss, but was ...
A major study of nearly 1,900 older adults suggests that stopping statins after age 70 may be relatively safe in the short term for people who have never experienced a heart attack or stroke. However, a higher rate of serious cardiovascular events ...
Researchers have uncovered a surprising hidden function of a protein that may hold the key to repairing damaged muscles and treating muscular dystrophy. Known for protecting chromosomes, TRF2 also helps muscle stem cells maintain their identity and ...
A surprising new study suggests that where men get their protein may be linked to their testosterone levels. Researchers studying more than 2,500 men found that higher animal protein intake, particularly from dairy, was associated with lower ...
Colorectal cancer is making an alarming comeback in the United States after more than 20 years of declining rates, and the increase is no longer limited to younger adults. A major new study found ...
Scientists have developed an AI-powered approach that makes experimental bionic vision technology more precise, helping predict the flashes and shapes of light perceived by a blind man with a brain implant. By learning how an individual's brain ...
An NIH study found that women with high levels of two common “forever chemicals” had up to 93% higher rates of an aggressive form of breast cancer. The discovery raises concerns about the ...
Scientists have uncovered a surprising way that fructose, a sugar commonly found in sweetened foods and drinks, may help aggressive ovarian cancer spread. Researchers discovered that cancer cells ...
A surprising new study suggests that walking, jogging, and even traditional weight training may be less effective at stimulating bone formation than high-intensity sports involving explosive movements and sudden changes in direction. Researchers ...
A new study found that energy drinks and stimulant supplements were linked to disproportionately frequent reports of serious heart problems, including 11 times more reports of cardiac arrest and 4.5 times more reports of heart attacks. Young adults ...
A surprising study of more than 4,500 older adults found that people who were overweight or obese when diagnosed with dementia had a 16% to 27% lower risk of death than those at a normal weight. Researchers suspect that extra energy and muscle ...

Latest Headlines

updated 12:56 pm ET