Question

Given below is a list of different steps (i-vi) involved in respiration.
(i) Utilisation of $O_2$ by the cells for catabolic reactions.
(ii) Transport of gases by the blood.
(iii) Pulmonary ventilation by which atmospheric air is drawn in and $C{O}_2$ is released out.
(iv) Released resultant $C{O}_2$.
(v) Diffusion of $O_2$ and $C{O}_2$ between blood and tissues.
(vi) Diffusion of gases ($O_2$ and $C{O}_2$) across alveolar tissues.
Select an option that has the correct sequence of all the steps.

• A. (iii), (vi), (ii), (v), (i), (iv)
• B. (iii), (vi), (i), (v), (ii), (iv)
• C. (iv), (ii), (v), (iii), (i), (v)
• D. (iv), (vi), (ii), (v), (i), (iii)

Answer 1

The correct option is A (iii), (vi), (ii), (v), (i), (iv)

The sequence of steps of respiration is:

• Pulmonary ventilation by which atmospheric air is drawn in and $C{O}_2$ is released out.
• Diffusion of gases (O${}_2$ and CO${}_2$) across alveolar tissues.
• Transport of gases by the blood.
• Diffusion of O${}_2$ and CO${}_2$ between blood and tissues.
• The utilization of O${}_2$ by the cells for catabolic reactions.
• Released resultant CO${}_2$.

So, the correct answer is '(iii), (vi), (ii), (v), (i), (iv)'.