MICROANATOMY

Detailed explanation-1: -Following maximal inspiration, the volume of air that leaves the lungs during a maximal force expiration is known as the vital capacity (VC). VC is composed of the tidal volume, expiratory reserve volume (ERV), and inspiratory reserve volume (IRV).

Detailed explanation-2: -Total Lung Capacity The vital capacity (VC) is the maximal volume of gas exhaled during a forced exhalation after a forced inhalation. Thus VC is the sum of the VT, IRV, and ERV. The VC is approximately 4.5 L in a healthy 70-kg adult.

Detailed explanation-3: -Expiratory reserve volume (ERV) is the amount of air that can be forcibly exhaled beyond a tidal exhalation (about 1200 ml for men & 700 ml for women).

Detailed explanation-4: -Residual volume (RV) is the volume of air remaining in the lungs after maximum forceful expiration. In other words, it is the volume of air that cannot be expelled from the lungs, thus causing the alveoli to remain open at all times.

Detailed explanation-5: -During normal breathing, the volume of air inspired or expired is known as Tidal volume. Its value is approximately 500 ml.