The presence of a red pigment called haemoglobin in red blood cells (RBC) makes the blood look red.
Haemoglobin is a protein that forms a complex along with iron molecules and carries oxygen molecules across the body. Iron can reflect red light, and blood looks red because our blood contains so much iron. Thus, haemoglobin makes the blood look red. It is the carrier of oxygen in our body.
Three types of haemoglobin
- Haemoglobin A. This is the most common type of haemoglobin found normally in adults.
- Haemoglobin F (fetal haemoglobin). This type is normally found in fetuses and newborn babies.
- Haemoglobin A2. This is a normal type of haemoglobin found in small amounts in adults.