INSPIRATION (IN-HALE)

EXTERNAL INTERCOSTAL CONTRACT TO PULL RIBS UP AND OUT INTERCOSTAL MUSCLES RELAX DIAPHRAGM CONTRACTS TO MOVE DOWN AND FLATTENS AIR PRESSURES DROPS AS AMSOPHERIC PRESSURE RISES ABOVE LUNG VOLUME INCREASES AIR MOVES INTO LUNGS AS THE ATMOSPHRTIC PRESSURE IS HIGHER THAN VOLUME OF THORAX (IN- INTERCOSTAL RELAX - EXTERNAL CONTRACT)