26. Fluid and Electrolyte Balance, Acid Base Balance

The control of blood pH by the kidneys during acidosis involves 

(a) The secretion of hydrogen ions and reabsorption of bicarbonate ions from the tubular fluid

(b) A decrease in the amount of water reabsorbed

(c) Hydrogen ion reabsorption and bicarbonate ion loss

(d) Potassium ion secretion

The drug Diamox is sometimes used to treat mountain sickness. Diamox inhibits the action of carbonic anhydrase in the proximal convoluted tubule. Polyuria (excessive urine production resulting in frequent urination) is a side effect associated with the medication. Why does polyuria occur?

David’s grandfather suffers from hypertension. His doctor tells him that part of his problem stems from renal arteriosclerosis. Why would this cause hypertension?

The most important factor affecting the pH of body tissues is the concentration of:

(a) Lactic acid

(b) Ketone bodies, 

(c) Metabolic acids

(d) Carbon dioxide

(e) Hydrochloric acid

While visiting a foreign country, Milly inadvertently drinks some water, even though she had been advised not to. She contracts an intestinal disease that causes severe diarrhea. How would you expect her condition to affect her blood pH, urine pH, and pattern of ventilation?

Write the missing names and molecular formulas for the following reactions between the carbonic acid–bicarbonate buffer system and the bicarbonate reserve.

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a. ___

b. ___

c. ___

Changes in the pH of body fluids are compensated for by all of the following except:

(a) An increase in urine output

(b) The carbonic acid–bicarbonate buffer system

(c) The phosphate buffer system

(d) Changes in the rate and depth of breathing

(e) Protein buffers

When the pH of body fluids begins to decrease, free amino acids and proteins will 

(a) Release a hydrogen from the carboxyl group

(b) Release a hydrogen from the amino group

(c) Release a hydrogen at the carboxyl group

(d) Bind a hydrogen at the amino group

In a protein buffer system, if the pH increases:

(a) The protein acquires a hydrogen ion from carbonic acid

(b) Hydrogen ions are buffered by hemoglobin molecules

(c) A hydrogen ion is released and a carboxylate ion is formed

(d) A chloride shift occurs

Define and give an example of:

(a) A volatile acid

(b) A fixed acid, and 

(c) A metabolic acid

Which represents the greatest threat to acid-base balance? Why?