Cells of Ideal Design

Red blood cells make up the majority of all blood cells. An adult male blood contains thirty billion red cells, which would be enough to cover almost half the surface of a soccer field. These cells give color to our blood and therefore to our skin.

Red cells look like discs. Due to their incredible flexibility, they can squeeze through capillaries and the minutest holes. If they were not so flexible, they would surely be stuck in various areas of the body. A capillary is normally four to five micrometers in diameter, whereas a red cell is about 7.5 micrometers (one micrometer is one thousandth of a millimeter, which is 0.000039 inch).

What would happen if red cells were not created with such flexibility? The researchers of diabetes gave some answers to this question. In diabetic patients, red blood cells loose their flexibility. This situation frequently gives way to clogging with inflexible red blood cells in the delicate tissues of the patients' eyes, which can lead to blindness.