Transplantable organs include the kidneys, liver, heart, lungs, pancreas and intestine. As for tissue, skin is used as a temporary dressing for burns, serious abrasions and other exposed areas. Bone is used in orthopedic surgery to facilitate healing of fractures or prevent amputation. Heart valves are used to replace defective valves. Tendons are used to repair torn ligaments on knees or other joints. Veins are used in cardiac by-pass surgery. Corneas can restore sight.