A medical procedure where a biological organ is transferred from one person to another is known as surgical transplantation. Organs such as hearts and lungs are removed from donors following death and transported to recipients but some organs, such as kidneys and livers, can be transferred from live donors. Bone marrow can be transplanted between a donor and recipient or removed from a patient, supplemented in a laboratory, and returned to the same patient in a procedure known as an autologous stem cell transplant.