Buffer Function
The blood has a ph value between 7.35 and 7.45. The metabolic processes of the blood depend on this value being maintained.
On the other hand, degradation products of the cells or nutrients from the digestive system are constantly absorbed by the blood. These have an effect on the pH value.
Therefore, there are regulatory forces in the blood that prevent the ph value from exceeding or falling below. These are the buffer systems. By buffer systems we mean mixtures of weak acids and strong bases or vice versa. They are able to counteract pH changes in the blood by binding free hydrogenions (H+) or hydroxide ions (OH -) excesses.