Explain how the structure of red blood cells is adapted for the transport of oxygen to body tissues.
A circulating red blood cell is metabolically active, but its lifespan is only about 120 days. Over this period, key enzymes are slowly broken down, which can help lead to cell death. Explain why the red blood cell cannot replace enzymes that have been lost.
Red blood cells are phagocytosed by cells in the liver and spleen. Their haemoglobin is then separated into haem and globin for further processing. Some of the breakdown products are reused by the body.
Name the mineral ion produced when haem is broken down.
State the products formed when globin is hydrolysed.
State the name of the enzyme that catalyses the reaction at X.
With reference to Fig. 3.1, describe and explain the part played by carbon dioxide ($\text{CO}_2$) and hydrogen ions ($\text{H}^+$) in the release of oxygen from haemoglobin.