Question

Which sheet-like muscle forms the floor of the chest cavity and is responsible for breathing?A. abdominalsB. diaphragmC. pectoralisD. deltoideus

Answer 1

There is one muscle that's mainly responsible for breathing. It contracts rithmically and continualy. It contracts during inhalation and relaxes during exhalation. It's the diaphragm. Therefore, the correct answer is B. diaphragm.