Biology: The Dynamic Science (MindTap Course List)
4th Edition
ISBN: 9781305389892
Author: Peter J. Russell, Paul E. Hertz, Beverly McMillan
Publisher: Cengage Learning
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Chapter 2, Problem 1ITD
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 184:459–469.
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Chapter 2 Solutions
Biology: The Dynamic Science (MindTap Course List)
Ch. 2.1 - Distinguish between an element and an atom, and...Ch. 2.2 - Prob. 1SBCh. 2.2 - Prob. 2SBCh. 2.2 - Prob. 3SBCh. 2.3 - Prob. 1SBCh. 2.3 - Prob. 2SBCh. 2.3 - Prob. 3SBCh. 2.3 - Prob. 4SBCh. 2.4 - Prob. 1SBCh. 2.4 - Prob. 2SB
Ch. 2.5 - Prob. 1SBCh. 2.5 - Why are buffers important for living organisms?Ch. 2 - Which of the following statements about the mass...Ch. 2 - Oxygen (O) is a(n) _______; the oxygen we breathe...Ch. 2 - The chemical activity of an atom: a. depends on...Ch. 2 - When electrons are shared equally between atoms,...Ch. 2 - Which of the following is not a property of water?...Ch. 2 - The water lattice: a. is formed from hydrophobic...Ch. 2 - A hydrogen bond is: a. a strong attraction between...Ch. 2 - Apply Evolutionary Thinking What properties of...Ch. 2 - If pond water has a pH of 5, the hydroxide...Ch. 2 - Prob. 10TYKCh. 2 - Prob. 11TYKCh. 2 - Prob. 12TYKCh. 2 - Discuss Concepts You place a metal pan full of...Ch. 2 - Prob. 14TYKCh. 2 - Prob. 15TYKCh. 2 - The pH of human stomach acid ranges from 1.0 to...Ch. 2 - Prob. 2ITDCh. 2 - Prob. 3ITD
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