In humans, respiration occurs in the following steps. Arrange these steps in the correct order. A. Diffusion of O2 and CO2 between blood and tissues B. Diffusion of O2 and CO2 across alveolar membrane C. Pulmonary ventilation by which atmospheric air is drawn in and CO2 rich alveolar air is released out D. Cellular respiration E. Transport of gases by the blood Choose the correct answer from the options given below:
Answer: (C) C, B, E, A, D. Answer: (c) C, B, E, A, D Solution: NCERT lists respiration steps in order: (i) pulmonary ventilation drawing in air [C], (ii) diffusion of gases across the alveolar membrane [B], (iii) transport of gases by the blood [E], (iv) diffusion of O2 and CO2 between blood and tissues [A], and (v) utilisation of O2 by cells, i.e., cellular respiration [D].
- A.A, B, C, D, E
- B.E, A, C, D, B
- C.C, B, E, A, D✓
- D.C, A, B, E, D
Correct Answer
(C) C, B, E, A, D
Solution & Explanation
Answer: (c) C, B, E, A, D Solution: NCERT lists respiration steps in order: (i) pulmonary ventilation drawing in air [C], (ii) diffusion of gases across the alveolar membrane [B], (iii) transport of gases by the blood [E], (iv) diffusion of O2 and CO2 between blood and tissues [A], and (v) utilisation of O2 by cells, i.e., cellular respiration [D]. This gives the order C, B, E, A, D. NCERT: Ch 14, p.185, line 21 — "Breathing or pulmonary ventilation by which atmospheric air is drawn in"