Tidal Volume and Minute Ventilation—NEET Biology

Correct answer: C — S1, S2 and S5 are correct

The core concept tested is the definition and typical values of various respiratory volumes and capacities, including the minute ventilation and the limitations of spirometry. S1: Correct. According to NCERT, a healthy human breathes 12-16 times/minute, and the Tidal Volume is approximately 500 mL. S2: Correct. The total volume of air inspired or expired per minute (minute ventilation) is the breathing rate multiplied by Tidal Volume. For a healthy man, this ranges from approximately (12 x 500 mL) 6000 mL to (16 x 500 mL) 8000 mL per minute. S3: Incorrect. Inspiratory Capacity (IC) is the total volume of air a person can inspire after a normal expiration, which includes Tidal Volume (TV) and Inspiratory Reserve Volume (IRV), not Expiratory Reserve Volume (ERV). S4: Incorrect. Residual Volume (RV) is the volume of air remaining in the lungs even after a forcible expiration. However, it cannot be measured directly by a spirometer. S5: Correct. Vital Capacity (VC) is defined as the maximum volume of air a person can breathe in after a forced expiration (IC + ERV = TV + IRV + ERV) or the maximum volume of air a person can breathe out after a forced inspiration (TV + ERV + IRV). Based on the analysis, statements S1, S2, and S5 are correct.