Apodeme -

An is an internal, ridge-like or finger-like ingrowth of the arthropod exoskeleton that provides a site for muscle attachment. Functionally, it is the invertebrate equivalent of a tendon , serving as a mechanical link that converts muscle contractions into limb or body movement. Anatomical Structure and Composition

The difference between (hardened) and flexible apodemes. apodeme

Because arthropods have an exoskeleton, their muscles cannot attach to internal bones like vertebrates. Apodemes provide these necessary attachment points on the inside of the hard outer shell. An is an internal, ridge-like or finger-like ingrowth

Broad, ridge-like or flange-like internal structures. Apophyses: Thinner, finger-like projections. Because arthropods have an exoskeleton, their muscles cannot

By providing specific anchor points, apodemes allow for the leverage needed to move heavy or resistant parts of the body efficiently.

Apodemes are formed by the invagination (inward folding) of the cuticle.

Like mammalian tendons, some apodemes have elastic properties. In jumping or running insects (like locusts), they can store elastic strain energy that is released rapidly to power explosive movements.