(a)[6]
Compare the number of people with COPD in cities and in villages, and suggest reasons for the differences. Use data from Fig. 2.1 to back up your answer.
(b(i))[4]
Explain how the body stops particles in inspired air from reaching the gas exchange surfaces.
(b(ii))[2]
State two ways in which inspired air differs in composition from expired air.
(c(i))[1]
State the name of the muscles that make the ribs move during ventilation.
(c(ii))[1]
During inspiration, the pressure and volume in the thorax change. State these changes. pressure ………………… volume …………………