Although the pH of blood ranges from 7.35-7.45, the pH of other body fluids is different. pH indicates the level of H+ ions, where low pH indicates too many H+ ions and high pH indicates too many OH- ions. Different organs function at their optimal level of pH. For example, the enzyme pepsin requires low pH to act and break down food, while the enzymes in intestine require high pH or alkaline environment to function. Similarly, any increase or decrease in the blood pH can lead to several disorders. pH is maintained in the body using primarily three mechanisms: buffer systems, respiratory control, and renal control.The abnormalities in acid-base balance are of two types: acidosis and alkalosis. In acidosis, the blood pH is low or there is too much acid in the blood, while in alkalosis, the blood pH is high or there is too much base in the blood. Acidosis and alkalosis may be caused either due to imbalance of acid-base secretion by the kidneys or altered levels of CO2 in the blood due to breathing disorders.

1. MS.SHILPI DAMOR
ASSISTANT PROFESSOR,DEPTT. OF ZOOLOGY
PODDAR GROUP OF INSTITUTIONS,JAIPUR

2. • Acids:-are substances that dissociate or lose ions.
• Bases:-are substances capable of accepting ions.
• Buffer:-is substance that reacts with acids and
bases to maintain neutral environment of stable
PH.
• pH:-represent the free hydrogen ions
concentration.

3. One part
acid
part 20
base
=

5. The body has three mechanisms to maintain
acid-base balance:
• Buffering mechanism.
• The respiratory compensation mechanism.
• The metabolic or renal compensation
mechanism.

7. • Acid-base buffer is defined as a solution
containing two or more chemical
compounds that prevent marked change in
hydrogen ions.
• Buffers act immediately to trap(
H+)temporarily until respiratory and renal
mechanism act. They only minimize the
change in(H+)concentration.

8. 1- Bicarbonate buffer system.
2- Phosphate buffer system.
3- Protein buffer system.
a- Plasma proteins.
b- Hemoglobin.
c-Tissue proteins.

40. Respiratory acidosis.
Respiratory alkalosis.
Metabolic acidosis.
Metabolic alkalosis.

41. 25