THORAX ABDOMEN AND PELVIS

Detailed explanation-1: -The diaphragm, located below the lungs, is the major muscle of respiration . It is a large, dome-shaped muscle that contracts rhythmically and continually, and most of the time, involuntarily. Upon inhalation, the diaphragm contracts and flattens and the chest cavity enlarges.

Detailed explanation-2: -In regular respiration, the genioglossus and other muscles of the floor of the mouth, such as the hypoglossus, are electrically involved in coordination with the diaphragm, immediately before contraction of the diaphragm itself.

Detailed explanation-3: -The diaphragm, a dome-shaped sheet of muscle that separates the chest cavity from the abdomen, is the most important muscle used for breathing in (called inhalation or inspiration). The diaphragm is attached to the base of the sternum, the lower parts of the rib cage, and the spine.