Haemoglobin

Haemoglobin

General Overview

• Haemoglobin is a red protein responsible for transporting oxygen in the blood.
• It is found in abundace in red blood cells.

Structure

• Each haemoglobin molecule is made up of four protein chains (two alpha and two beta chains).
• Each protein chain contains one haem molecule which has an iron (Fe) atom at its centre.
• The iron atom present in the haem molecules allows haemoglobin to bind with oxygen and transport it around the body.

Function

• A primary function of haemoglobin is to transport oxygen from the lungs to the rest of the body.
• At the lungs, haemoglobin binds with oxygen to form oxyhaemoglobin.
• Oxyhaemoglobin then travels through the circulatory system, releasing the oxygen to cells and tissues that require it.
• After releasing oxygen, haemoglobin picks up carbon dioxide, a waste product of cellular metabolism, to form carboxyhaemoglobin. This is then transported back to the lungs for exhalation.

Affinity for Oxygen

• Haemoglobin’s affinity for oxygen changes depending on the conditions.
• For example, at the high oxygen levels in the lungs, haemoglobin has a high affinity for oxygen, allowing it to pick oxygen up readily.
• At low oxygen levels found in active tissues, haemoglobin’s affinity for oxygen decreases, releasing oxygen where it’s required for cellular respiration.

Reminisce: Haemoglobin is crucial to our survival due to its role in oxygen transport!