Which Lineage of Echinoderms Is Made Up of Sea Stars

question 129

Multiple Choice

Which lineage of echinoderms is made up of sea stars, each with a central disk surrounded by 5 to 20 "arms"?

• A) Ophiuroidea
• B) Asteroidea
• C) Crinoidea
• D) Echinoidea

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Definitions:

Linea Alba

A fibrous structure that runs down the midline of the abdomen, providing attachment for abdominal muscles.

Serratus Anterior

The serratus anterior is a muscle that originates on the surface of the 1st to 8th ribs at the side of the chest and inserts along the entire anterior length of the medial border of the scapula, playing a crucial role in the movement of the shoulder blade.

Rectus Abdominis

A major abdominal muscle that helps in movements of the trunk and stabilizes the pelvis.

External Oblique

A muscle located on the external surface of the abdomen, part of the abdominal wall muscles, playing a role in trunk movement and support.