Input System Output Oxygen/Carbon Dioxide Kidney Erythropoietin (EPO) Erythropoietin (EPO) Bone marrow Red blood cells Cellular damage Liver C-reactive protein (CRP) C-reactive protein (CRP) Bone marrow Neutrophils (White blood cells) Unconjugated bilirubin Liver Conjugated bilirubin Antigen T-cell lymphocyte ‘Wanted Poster’ complex ‘Wanted Poster’ complex B-cell lymphocyte Antibody Thyroid-stimulating hormone Thyroid Thyroxine

Draw a network diagram to show oxygen levels and kidney production of EPO, which induces the bone marrow to make more red blood cells which should carry more oxygen around, thereby reducing the need for more EPO. You can annotate this by adding a family group onto each organ or system.