The mechanism of respiration

Rib movements in breathing Inhaling

Chest

Chest

Back

Exhaling

Exhaling

Lungs

Back

Chest

Lungs

Chest

Back

Inhaling. The diaphragm and intercostal muscles contract, pulling the ribs upward. This increases the volume of the chest cavity, drawing air into the lungs.

How the diaphragm works Inhaling ^^

Exhaling. The contracted muscles relax, the ribs fall slightly and decrease the volume of the chest. Air is forced out of the lungs.

Exhaling

Exhaling

Inhaling. As the rib cage expands (arrows, above), the diaphragm contracts and flattens downwards, enlarging the chest cavity.

Exhaling. The diaphragm relaxes and is pressed up by the abdominal organs, returning to its dome shape. The chest narrows, driving air out of the lungs.

Fig 7.4 The mechanism of respiration

The major muscle of respiration is the diaphragm. The mechanism of respiration is the means by which air is drawn in and out of the lungs. It is an active process where the muscles of respiration contract to increase the volume of the thoracic cavity.

study tip

How To Reduce Acne Scarring

How To Reduce Acne Scarring

Acne is a name that is famous in its own right, but for all of the wrong reasons. Most teenagers know, and dread, the very word, as it so prevalently wrecks havoc on their faces throughout their adolescent years.

Get My Free Ebook


Post a comment