AP BIOLOGY

Detailed explanation-1: -These muscles are found between the ribs, and there are two kinds: the internal and external intercostals. The internal intercostal muscles (in the inside of the ribcase) extend from the front of the ribs, and go around back, past the bend in the ribs.

Detailed explanation-2: -The movement of the rib cage is controlled by the intercostal muscles, and the diaphragm is a skeletal muscle. During inspiration the diaphragm and the external intercostal muscles contract, causing an increase in the thoracic cavity volume.

Detailed explanation-3: -The muscles that make up the thorax wall include the three intercostal muscles (external, internal, and innermost), the subcostalis, and the transversus thoracis. Eleven pairs of intercostal muscles are in each of the intercostal spaces, arranged from superficial to deep.

Detailed explanation-4: -There are 3 muscular layers in each intercostal space, consisting of the external intercostal muscle, the internal intercostal muscle, and the thinner innermost intercostal muscle. These muscles help to move the ribs during breathing.

Detailed explanation-5: -Your intercostal muscles lie between your ribs, attaching them to one another. They help stabilize your upper body and help you breathe. There are three layers of intercostal muscles: the external intercostals, the internal intercostals, and the innermost intercostals.