Question

Identify the correct and incorrect match about respiratory volume and capacities and mark the correct answer.
i. Inspiratory capacity (IC) = Tidal Volume + Residual Volume
ii. Vital Capacity (VC) = Tidal Volume (TV) + Inspiratory Reserve Volume (IRV) + Expiratory Reserve Volume (ERV).
iii. Residual Volume (RV) = Vital Capacity (VC) - Inspiratory Reserve Volume (IRV)
iv. Tidal Volume (TV) = Inspiratory Capacity (IC) - Inspiratory Reserve Volume (IRV)

• A. (i) Incorrect, (ii) Incorrect, (iii) Incorrect, (iv) Correct
• B. (i) Incorrect, (ii) Correct, (iii) Incorrect, (iv) Correct
• C. (i) Correct, (ii) Correct, (iii) Incorrect, (iv) Correct
• D. (i) Correct, (ii) Incorrect, (iii) Correct, (iv) Incorrect

Answer 1

Answer: (B)

Inspiratory capacity is the amount of air inhaled during normal breathing and also during forceful breathing. Thus $IC \, = \, TV \, + \, IRV$
Residual volume is the amount of air left in the lungs after forceful breathing.
Thus $RV \, = \, FRC \, -ERV$
Tidal volume is amount of air inhaled or exhaled during normal breathing
$TV \, = \, IC \, - \, IRV \, \left(\right. \, IC \, is \, TV \, + \, IRV\left.\right)$
Vital capacity includes all the volumes except tidal volume.