AP BIOLOGY

Detailed explanation-1: -n. Symmetrical about an axis that runs from the oral surface where the mouth is to the side opposite the mouth. Cnidarians have radial symmetry. Echinoderms are bilateral animals that have a 5-part radial symmetry as adults.

Detailed explanation-2: -Characteristics of Echinodermata They have a star-like appearance and are spherical or elongated. They are exclusively marine animals. The organisms are spiny-skinned. They exhibit organ system level of organization.

Detailed explanation-3: -One characteristic of an echinoderm is that they all have pentamerous radial symmetry. This simply means they all have 5 equal body parts. You can divide these animals into five equal parts, and every part is the same. For example, most sea stars have five arms or a multiple of five arms.