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Human Body Study

Mammary Glands

The breasts — paired glands on the chest wall that produce milk after birth. Present in both sexes but only functional in females following pregnancy.

Female reproductive system Front-view schematic showing the mammary glands, ovaries, fallopian tubes, uterus, and the cervix and vagina; each labelled part links to its article. Female reproductive system Mammary glands the breasts, which produce milk after birth. Ovaries produce eggs and the hormones estrogenand progesterone. Fallopian tubes carry the egg toward the uterus; theusual site of fertilization. Uterus the muscular organ where a fertilizedegg implants and a fetus develops. Cervix and vagina the lower passage; the vagina is alsothe birth canal. Female reproductive system — schematic front view, not to scale.

Structure

Section titled “Structure”
  • Lobules — clusters of milk-secreting cells.
  • Ducts — tubes that carry milk from the lobules to the nipple.
  • Areola and nipple — the pigmented circle and the central outlet.
  • Adipose tissue — gives the breast its bulk and shape.

What they do

Section titled “What they do”
  • Lactation — produce and deliver milk for the infant after childbirth.
  • Hormonally driven — milk production is triggered by prolactin; milk release (the let-down reflex) is triggered by oxytocin.

Key idea

Section titled “Key idea”

Anatomically, the mammary glands are modified sweat glands of the integumentary system; functionally, they belong to the reproductive system because they feed the next generation.