Red blood cell and are able to interface with immune cells. Their membrane plays many roles in this. These functions are highly dependent on the membrane composition. The red blood cell membrane is composed of 3 layers: the glycocalyx on the exterior, which is rich in carbohydrates; the lipid bilayer which contains many transmembrane proteins, besides its lipidic main constituents; and the membrane skeleton, a structural network of proteins located on the inner surface of the lipid bilayer. Half of the membrane mass in human and most mammalian red blood cells are proteins. The other half are lipids, namely phospholipids and cholesterol. The
Blood red wound, and it does not change color upon exposure to air. The color "blood red", therefore, covers both these states: the darker deoxygenated color and the brighter oxygenated one. Also, dried blood often has a darker, rust-colored quality: all dried blood has been oxygenated and then desiccated, causing the cells within it to die. This blood is often darker than either shade of red that can be seen in fresh blood. In the RGB color spectrum blood red often consists only of the color red, with no green or blue component; in the CYMK color model blood red has no