Download blood - SCH4U1-02-2010

Alice & Jill
BLOOD CHEMISTRY
Connections
1. Equilibrium
-Hemoglobin protein reacts with oxygen to form HbO2.
-Hemoglobin protein reacts with CO resulting in Carbon Monoxide poisoning.
2.
Redox reaction of the haemoglobin
The equilibrium reaction for the transport of oxygen by haemoglobin (Hb) can be
represented as:
Hb(aq) + O2(aq)
HbO2(aq)
OR
Hb4 (aq) + 4O2 (aq)
Hb4O8 (aq)
In the lungs where there is a high concentration of oxygen, by Le Chatelier's principle
the equilibrium position shifts to the right resulting in the formation of
oxyhaemoglobin (oxyhemoglobin).
In tissues the concentration of oxygen is lower, so the equilibrium position shifts to
the left, by Le Chatelier's principle. Oxyhaemoglobin releases oxygen to re-form
haemoglobin.
3. Le Chatelier's principle
-Le Chatelier’s principle explains how equilibrium reaction will shift as changes are
introduced to the system.
-This holds the key to understanding how buffers work in the body.
4. pH buffers in the blood
-By far the most important buffer for maintaining acid-base balance in the blood is the
carbonic-acid-bicarbonate buffer. This reaction helps to maintain the narrow range of
pH in the blood.
5. pH effects on blood
-We are interested in the change in the pH of the blood; therefore, we want an
Alice & Jill
expression for the concentration of H+ in terms of equilibrium constant
- The ideal pH level for blood is 7.35-7.45
- The higher the pH of a solution, the more electrical resistance that solution holds.
- If pH level is either alkaline or acid, you will become ill, perhaps even die.
6. Electrolyte
-Dietary Electrolytes and Blood Pressure.
Electrolyte is a "medical/scientific" term for salts, specifically ions. The term
electrolyte means that this ion is electrically-charged and moves to either a negative
(cathode) or positive (anode) electrode:


ions that move to the cathode (cations) are positively charged
ions that move to the anode (anions) are negatively charged