The diagram illustrates the gas exchange surface of a person who has recently smoked a cigarette. Substance P is able to cause cancer. What is substance P?
- Acarbon dioxide
- Bcarbon monoxide
- Cnicotine
- Dtar
Biology 0610 · IGCSE · Diseases and immunity
The diagram illustrates the gas exchange surface of a person who has recently smoked a cigarette. Substance P is able to cause cancer. What is substance P?