Respiration involves following steps

a) Diffusion of gases ($O_{2 }$and $C{O}_2$) across alveolar membrane

b) Transport of gases by blood

c) Utilization $O_{2 }$by the cells for catabolic reactions and resultant release of $C{O}_2$

d) Breathing or pulmonary ventilation by which atmospheric air is drawn in and $C{O}_2$rich alveolar air is released out

e) Diffusion of $O_{2 }$and $C{O}_2$between blood and tissues

The correct sequence of steps is

The correct sequence of steps involve in respiration is 

(i) Breathing or pulmonary ventilation by which atmospheric air is drawn in and CO₂ rich alveolar air is released out. 

(ii) Diffusion of gases (O₂ and CO₂ ) across alveolar membrane. 

(iii) Transport of gases by the blood. 

(iv) Diffusion of O₂ and CO₂ between blood and tissues. 

(v) Utilisation of O₂ by the cells for catabolic reactions and resultant release of CO₂