Human blood contains specialized cells, including erythrocytes (red blood cells) and leucocytes (white blood cells), which play vital roles in transport and defense.
The table below shows how different clinical and environmental situations affect the count of these blood cells:
| Situation | Number of functional red blood cells | Number of white blood cells |
|---|---|---|
| Suffering from chronic lead poisoning (which inhibits haem synthesis) | decreases | stays the same |
| Receiving regular injections of synthetic Erythropoietin (EPO) | increases | stays the same |
| Undergoing immunosuppressive therapy following an organ transplant | decreases | decreases |
Explain why chronic lead poisoning, which inhibits the enzyme required to synthesise haem, causes a reduction in the number of functional red blood cells.
Explain how the change in red blood cells from receiving synthetic Erythropoietin (EPO) injections benefits an endurance athlete during a long-distance cycling race.
Explain why a decrease in the number of white blood cells due to immunosuppressive therapy increases the patient's vulnerability to serious illness.
