Protein digestion in the stomach releases large amounts of urea. Urea is a nitrogenous breakdown product of amino acids. Helicobacter pylori takes advantage of this sea of urea and uses it for protection against the acidic environment of the stomach. The outer membrane of H. pylori is studded with enzymes called ureases. Urease converts urea into carbon dioxide and ammonia, which is a base. How does the conversion of urea into ammonia protect H. pylori from the hostile environment of the stomach?
Why does drinking water before, with, and after a meal help digestion? (“The water fairy” is not the correct answer.)
Why can the use of antibiotics lead to difficulty in blood clotting and diarrhea? ("The evil diarrhea fairy" is not the correct answer.)
What would happen to the body if filtration continued at a normal rate but reabsorption dropped to one-half of normal?
Explain how the regulation of urine concentration and volume is a negative feedback system.
Which procedure would have the most detrimental effect on digestion – removal of the stomach, pancreas, or gallbladder? Explain your choice.
Normally when the body becomes dehydrated it produces urine with more solutes and less water. Under the influence of alcohol a person will produce dilute urine even if they are becoming dehydrated. Explain why this is so in detail.
The metabolites of marijuana are small, nonpolar molecules. Marijuana metabolites usually can be detected in a person’s blood and urine for weeks after they have last used the drug. Explain why it takes the body so long to excrete all the metabolites of marijuana.
A physician prescribes an oral antibiotic for a patient with an infection of the urinary bladder. How would you describe for the patient the route the drug follows to reach the bladder?
If an infant is borne with narrowed renal arteries, what effect would this condition have on the volume of urine produced? Explain your answer.