Blood carry oxygen, instead of hemoglobin. Insects and some mollusks use a fluid called hemolymph instead of blood, the difference being that hemolymph is not contained in a closed circulatory system. In most insects, this "blood" does not contain oxygen-carrying molecules such as hemoglobin because their bodies are small enough for their tracheal system to suffice for supplying oxygen. Jawed vertebrates have an adaptive immune system, based largely on white blood cells. White blood cells help to resist infections and parasites. Platelets are important in the clotting of blood. Arthropods, using hemolymph, have hemocytes as part of their immune system. Blood
Genetically engineered blood Genetically engineered blood Genetically engineered blood is blood that has been modified for therapeutic or other purposes. Genetically modifying red blood stem cells allows them to produce specific therapeutic proteins on the surface or inside the cell. The stem cells are taken from mammalian bone marrow and are modified in culture. Before they become mature, mammalian red blood cells eject their genetic material. Culturing cells that produce a new protein of interest requires only a few weeks. Using the sortagging protein labeling technique, the researchers used the bacterial enzyme sortase A to establish a strong chemical bond between the surface