This experiment separates meat into an acetone-soluble part and an acetone-insoluble part. The calculations are based on the principal components of meat being fat (acetone soluble) and protein (acetone insoluble or fat-free meat in report sheet). More realistically, the principal components of meat are fat, protein, and water. Water is acetone soluble. Based on this information, the calculations correctly calculate what quantity, % fat or % fat-free meat? Is the incorrectly calculated quantity over or under estimated?

If phenylalanine was not an essential amino acid, would diet therapy (the elimination of phenylalanine from the diet) for PKU work?

The pH of human stomach acid ranges from 1.0 to 3.0, whereas a healthy esophagus has a pH of approximately 7.0. In gastroesophageal reflux disease (GERD), often called acid reflux, stomach acid flows backward from the stomach into the esophagus. Repeated episodes in which esophageal pH goes below 4.0, considered clinical acid reflux, can result in bleeding ulcers and damage to the esophageal lining. The data in the Figure, from a patient with GERD, show esophageal pH during a sleeping reflux event. How many minutes does it take to go from the peak of the reflux event (when pH is most acidic) to when the reflux event is over? Source: Based on T. Demeester et al. 1976. Patterns of gastroesophageal reflux in health and disease. Annals of Surgery 184:459469.