Page 25 - The Cell in 40 Topics

other's milk is one of the countless miracles that God has
created. The ingredients it contains meet all of a newborn
baby's nutritional needs. Furthermore, those ingredients change according
to the changing needs of the baby's developing body. The manufacturers of
this substance, the like of which scientists are unable to manufacture in
their laboratories, are particular cells in the mother's breast. These cells pos-
sess the matchless formula for mother's milk and know exactly when to
begin production and when to alter the makeup of the fluid they produce.
So how does the production of mother's milk begin, and how is it con-
trolled? In the answers to this question lie hidden many miracles of cre-
ation. The hormonal system and nervous system work together in milk
production, which in turn takes place as the result of a flawless flow of in-
formation and planning (Figure 13).
One very special hormone activates the milk glands in the mother's
breast. This is the hormone prolactin, secreted by the pituitary gland.
At the beginning of pregnancy, however, a number of factors restrict
the secretion of the hormone prolactin. We may think of these factors' func-

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