Describe Two Ways by Which Spiral Structure May Be Induced

question 70

Essay

Describe two ways by which spiral structure may be induced in a spiral galaxy's disk.

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Definitions:

Internal Intercostals

Muscles located between the ribs that assist with the process of respiration by decreasing the volume of the thoracic cavity during exhalation.

Superior Border

The uppermost edge or boundary of an anatomical structure.

Inferior Rib

Refers to the lower ribs in the human rib cage, possibly intended to distinguish them from upper ribs but not a standard anatomical term.

Transverses Thoracis

A muscle within the thorax that plays a role in the movement of the thoracic cage during respiration.