Electrically neutral molecules can pass through cell membranes more easily than charged molecules can. Aspirin has a carboxylic acid group with a pKa value of 3.5. In order to be absorbed into the bloodstream it must pass the membrane lining the stomach and intestine. Would you expect more aspirin to be absorbed in the stomach (pH 1) or in the small intestine (pH 6)?

Electrically neutral molecules can pass through cell membranes more easily than charged molecules can. Aspirin has a carboxylic acid group with a pKa value of 3.5. In order to be absorbed into the bloodstream it must pass the membrane lining the stomach and intestine. Would you expect more aspirin to be absorbed in the stomach (pH 1) or in the small intestine (pH 6)?

Human Physiology: From Cells to Systems (MindTap Course List)

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter1: Introduction To Physiology And Homeostasis

Section: Chapter Questions

Problem 2TAHL

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