NEETZoologyBreathing and Exchange of Gases
What is the first step in respiration?
Options
- AExchange of oxygen and carbon dioxide between deoxygenated blood and alveoli
- BTransport of gases throughout the body by blood
- CExchange of oxygen and carbon dioxide between oxygenated blood and tissues
- DBreathing
Correct answer
D. Breathing
Step-by-step solution
The first step in respiration is breathing by which atmospheric air is taken in (inspiration) and the alveolar air is released out (expiration). Respiration involves the following steps: (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 reactio