What organ system makes scabs?

As the clot starts to get hard and dries out, a scab forms. Scabs are usually crusty and dark red or brown. Their job is to protect the cut by keeping out germs and allowing the area underneath to heal. There isn't one organ system involved but at least three: cardiovascular system (blood), lymph (white blood cells eat bacteria, part of the immune system) and the skin (integumentary system) which acts as a Band-Aid.