Question

Write briefly about Bohr effect and Haldane effect and their significance.

Answer 1

Hint : The decrease in oxygen affinity of haemoglobin when the blood $pH$ decreases is called the Bohr effect and is related in a way that deoxygenated haemoglobin binds ${H^ + }$ more actively than oxyhaemoglobin. The increased capacity of deoxygenated haemoglobin to carry $C{O_2}$ is referred to as the Haldane effect.

Complete Step By Step Answer:
The Bohr Effect and its significance is stated below,
The pH of blood decreases as its $C{O_2}$ content increases, so that when the $PC{O_2}$ increases, the oxygen haemoglobin dissociation curve slides to the right and the ${P_{50}}$ increases.
Most of the unsaturation of haemoglobin occurs in the tissues is secondary to the lessening in the PO2, but an extra $1 - 2\%$ of haemoglobin’s unsaturation is due to the rise in $PC{O_2}$ and the consequent shift of the dissociation curve to the right.
The Bohr effect takes place in tissues that are metabolically active. This helps with the transport of oxygen from the haemoglobin molecule and it does work accurately to the metabolic activity of the tissue.
As more metabolism takes place, the partial pressure of carbon dioxide increases and will cause a lowered value in $pH$ and will allow for greater oxygen unloading.
This is especially true in exercising skeletal muscles which may also release lactic acid which in turn reduces local blood $pH$ and therefore enhances the Bohr Effect.
The Haldane effect and its significance is stated below,
De-oxygenated haemoglobin binds more ${H^ + }$ than oxyhaemoglobin and deoxygenated haemoglobin forms carbamino compounds more readily than oxyhaemoglobin.
The attachment of oxygen to haemoglobin reduces the capacity of haemoglobin to carry $C{O_2}$ . The reason for this is that ${O_2}$ increases the ionization of nitrogen groups, which reduces the capacity of the globin chain to carry $C{O_2}$ as carbamino compounds.
De-oxyhaemoglobin can carry more $C{O_2}$ in the form of carbamino compounds. Haemoglobin binds more ${H^ + }$ than oxyhaemoglobin. De-oxyhaemoglobin is more basic and therefore has an increased capacity excluding the ${H^ + }$ ions produced when carbonic acid dissociates and so has an increased buffering capacity for $C{O_2}$ .
Similarly, venous blood carries more $C{O_2}$ than arterial blood, and $C{O_2}$ uptake is more in the tissues and $C{O_2}$ release is increased in the lungs.

Note :
The Bohr and Haldane effects have got to do with the filling of oxygen to the haemoglobin molecule and the emptying of oxygen from the haemoglobin molecule Haemoglobin is red, ${O_2}$ carrying pigment in the red blood cells of vertebrates. There are about $200 - 300$ million haemoglobin molecules in each red blood cell.