What is the Bohr effect?
The correct answer and explanation is :
The Bohr effect, first described in 1904 by Danish physiologist Christian Bohr, refers to the physiological phenomenon where hemoglobin’s oxygen-binding affinity is inversely related to acidity (pH) and the concentration of carbon dioxide (CO₂) in the blood. In simpler terms, an increase in CO₂ levels or a decrease in pH leads hemoglobin to release oxygen more readily, whereas lower CO₂ levels or higher pH enhance hemoglobin’s ability to bind oxygen.
This mechanism is vital for efficient oxygen transport and delivery within the body. In the lungs, where CO₂ concentration is low and pH is relatively higher, hemoglobin binds oxygen effectively. Conversely, in metabolically active tissues, where CO₂ production is high and pH is lower, the Bohr effect facilitates the release of oxygen from hemoglobin, ensuring that oxygen is delivered to areas where it is most needed.
At the molecular level, the Bohr effect is influenced by allosteric interactions within the hemoglobin molecule. Hemoglobin can exist in two conformations: the high-affinity R state and the low-affinity T state. Increased levels of CO₂ and H⁺ ions stabilize the T state, promoting oxygen release. Additionally, CO₂ can bind directly to hemoglobin, forming carbamates that further stabilize the T state and contribute to the release of oxygen.
Understanding the Bohr effect is crucial in fields like physiology and medicine, as it explains how hemoglobin’s oxygen-binding affinity is modulated by changes in the body’s internal environment, thereby optimizing oxygen delivery during varying metabolic demands.
