What occurs to lung volume during inhalation?

During inhalation, lung volume increases as air is drawn into the lungs. This process occurs because the diaphragm contracts and moves downward, and the intercostal muscles between the ribs lift the rib cage upwards and outward. As the thoracic cavity expands, the pressure inside the lungs decreases relative to the outside atmosphere, allowing air to flow in.

When considering tidal volume, which is the amount of air inhaled or exhaled during normal breathing, it is accurate to say that during an inhalation, lung volume increases by one tidal volume. This is the standard volume of air exchanged in a single breath during quiet breathing, highlighting the change in lung capacity during this phase of respiration. Thus, recognizing that the primary change is the increase in lung volume is crucial for understanding the mechanics of breathing.