Animal Symmetry

Spherical Symmetry

Any plane passing through the center will divide the body into like halves

Radial Symmetry

Any plane passing through the longitudinal axis will divide the body into like halves

Bilateral Symmetry

Only a sagittal plane will divide the animal into like right and left halves (mirrored portions)

Asymmetry (no symmetry)

No plane will produce like halves

Sagittal

Toward or upon the SURFACE of the body

Analogous Structure

Structures that may be similar in function, but are not similar in structure and do not indicate a close evolutionary relationship.

Longitudinal

Pertains to the long axis of the body, often from “front” to “back”

Lateral

Away from the midline of the body, or pertaining to the side

Posterior

Toward the REAR off an animal, or opposite the front

Appendage

A(n) ___ is any structure that extends away from an organism’s body, such as an arm or wing

Analogous

Further from, or away, from and appendage’s origin or attachment

Coronal

A ___ plane divides the body into ventral and dorsal parts

Caudal

Of, toward, or related to the TAIL of an organism

Coronal

A ___ plane divides the body into anterior and posterior parts

Proximal

Found closer to the attachment or origin of an appendage

Anterior

Toward the FRONT end of an animal

Homologous Structure

These structures are similar in their make-up and structure, due to close evolutionary relationships.