Red blood cells are named after their most eye-catching characteristic – their color. The fact that the blood cells are red is due to the protein hemoglobin.

Hemoglobin is a very important protein. It can bind oxygen and thus enables the red blood cells to carry this essential gas throughout the whole body.

Although red blood cells have a discoid appearance, they can easily be deformed so that they squeeze through even the narrowest of blood vessels. During certain illnesses like sickle cell anemia, the red blood cells lose their ability to be deformed. This is a dangerous situation because some of the very narrow blood vessels are blocked by the rigid blood corpuscles. The fatal result is that some parts of the body are no longer supplied with sufficient amounts of oxygen and nutrients. Then the affected tissue cells cannot function properly any longer or even die.