Acid Based Homeostasis

Fluid, Electrolyte and Acid-Base Balance: Acid-Base Homeostasis

1. When we ↑ or ↓ the pH by one pH unit, we are changing the concentration of H+ by a factor of 10.

2. What is the pH of the following:

a. Arterial blood = 7.35 to 7.45.

b. Venous blood = 7.35. Why? caused by the presence of more carbonic acid.

c. Interstitial fluid = 7.35.

d. Cell = 7.0.

e. Gastric juices = 1.2 to 3.0. However, it is often buffered by the buffering effect of food.

f. Small intestines = 8.0. Why? the presence of bicarbonate ions.

g. Urine = 4.5 to 8.0. This is based on diet and metabolic state.

3. A substance is a strong acid if it release all their hydrogen ion in water. An example of a strong acid is aqueous solution of hydrochloric acid, or HCl-.

a. Possible pH is 1.0.

4. A substance is a weak acid if it does not completely dissociate. An example of a weak acid is carbonic acid, or H2CO3.

a. Possible pH is 4.5.

5. Lactic acid is also a weak acid, but it releases more H+ ions into the blood. It typically has a pH of 2.5.

6. Bases take up hydrogen ion (H+). There are both strong and weak bases, but only weak bases exist in the body.

An example is bicarbonate, or HCO3-.

7. Some electrolytes are acids and bases in the body.

a. Examples of weak bases are: bicarbonate ion, phosphate ion, sulfate, and organic acids

b. Dihydrogen phosphate is an example of an acid in the body.

c. Proteins have both acidic and basic side groups.

8. If pH is altered, some globular proteins (i.e. enzymes and hormones) lose their shape, or are denature and can no longer function properly. This will elicit clinical symptoms.10. List the three important buffer systems in the body:

a. carbonic acid/bicarbonate buffer system (carbonic acid/bicarbonate).

b. Dihydrogen phosphate buffer system (phosphate).

c. protein buffer system.

11. Write the equation showing the relationship of CO2 and H2O levels with bicarbonate...