Deuterostomes/ Echinodermata

1) Radial symmetry (pentamerous:5 parts)
2) has calcarious skeleton with spicules
3) sea urchins, brittlestars, and starfish,

Star fish

1) madreporite that opens into the water‑vascular system
2) anus is located in the interradius clockwise from the madreporite
3) bivium arms: The rays on either side of the madroporite
4) trivium arms: Remaining 3 armes
5)surface covered in cilia and calcareous tubercles, spines, and beak‑like pedicellaria

1) testes or ovaries of Asterias are paired organs located in each ray
2) five radial vessels located in podia and ampulla

• Mucous net method. The animal assumes a feeding posture with arm tips raised and spines spread. Mucous glands secrete strings of mucus that hang over the spines. The arms are then swept through the water column and the plankton‑laden net is moved to the mouth by podia and/or cilia).
• Surface film feeding. The animal will move its arms parallel to the surface and the podia pick up particulate matter.

• Arm‑loop captures. The arms may flex around large particles and convey them directly to the mouth
• Browsing. Rarely, an animal will move over the substrate directly picking up food with its mouth

Tubefoot capture. Intermediate sized particles are picked up by the tube feet and passed directly to the mouth.

Sea cucumber

1) polian vesicles: ring canal has two elongate sacs that are thought to be reservoirs of water vascular fluid.
2) respiratory trees two large branching organs that lead out of the terminal end of the intestine.
3) mouth, pharynx, esophagus, stomach, intestine, and cloaca.

Sea urchin

1) 5 protrusible teeth
2)5 gills
3) the aboral surface locate the periproct, madroporite and genital plates
4) ambulacra : the tube feet on the urchin are restricted to five bands on the test

Acorn worm

Acorn worm

A

dorsal hollow nerve cord, notochord, pharyngeal gill slits, and a post anal tail

Sea squirt