Verily in cattle, there is lesson for you; We give you to drink of what is inside their bellies coming from a conjunction between the contents of the intestine and blood, a milk, pure and pleasant for those who drink it." (The Quran, 16:66, translation by Maurice Bucaille)

The Holy Quran here describes the biological process in the mammals which brings together the contents of the intestine and the blood at the level of the intestinal wall, which produces milk. This is in perfect harmony with recent discoveries made in physiology of the digestive system of mammals. Such minute and specific knowledge was totally unknown to mankind when the Holy Quran was revealed!