AP BIOLOGY

Detailed explanation-1: -The major muscle group for exhalation is made up of the internal intercostals. These muscles pull down on the rib cage and thereby push air out of the lungs.

Detailed explanation-2: -Abdominal muscles contract, raise abdominal pressure, and push a relaxed diaphragm against the lungs, causing air to be pushed out.

Detailed explanation-3: -The contraction of Intercostal muscles or internal intercontinental muscles in man causes expiration. Expiration or exhalation is the flow of the breath out of an organism.

Detailed explanation-4: -The diaphragm (DYE-uh-fram) is a muscle between the chest and the abdomen that allows the body to move air in and out of the respiratory system. When you breathe in (inhalation), the diaphragm moves down toward the abdomen, and the rib muscles pull the ribs upward and outward.

Detailed explanation-5: -The innermost intercostal muscles relax, while the external intercostal muscles contract, causing the chest cavity to expand. This expansion allows the lungs to fill with air, due to the negative pressure created by the extra space. Air fills the lungs, gases are exchanged, and it is time to exhale.