Chapter 32 Deuterostome

Deuterostome

A group of animals in which the mouth forms second during embryonic development.

Echinoderm

A marine invertebrate with an exoskeleton, radial symmetry as adults, and a water vascular system with tube feet.

Chordate

An animal that possesses a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail at some point in its life cycle.

Vertebrate

A member of the phylum Chordata that has a backbone, including hagfish, lampreys, and all groups of bony and cartilaginous fishes, amphibians, mammals, and reptiles.

Amniotic egg

An egg with membranes that provide support, nutrition, and waste disposal, crucial for the development of amniotes.

Neural crest cells

Specialized embryonic cells that give rise to structures such as jaws and gill supports in vertebrates.

Pentaradial symmetry

A type of radial symmetry found in adult echinoderms, characterized by a five-part organization.

Aristotle’s lantern

A feeding apparatus in sea urchins composed of five calcium carbonate teeth used for grazing.

Coelom

The body cavity in metazoans which develops from outpockets of mesoderm in deuterostomes.

Endoskeleton

A hard structure located just inside a thin layer of epidermal tissue in echinoderms that provides support and protection.