Fig. 5.1 shows some of the structures of the human gas exchange system that tobacco smoke travels through. Describe the gross structure of the human gas exchange system.
Shortly after smoking stops, the short-term actions of nicotine are reversed. State the changes that will happen in the cardiovascular system because nicotine levels are lower.
Fig. 5.2 presents oxygen dissociation curves for adult haemoglobin. Curve A shows measurements taken from a heavy smoker. Curve B shows measurements taken several weeks after the same individual stopped smoking. With reference to Fig. 5.2, describe and explain how these results demonstrate some of the health benefits of stopping smoking.
A person who stops smoking lowers their risk of developing lung cancer, a non-infectious disease. Explain why lung cancer is described as non-infectious.