Final answer:
The phylum Chordata includes both invertebrate and vertebrate groups, encompassing species like tunicates, lancelets, and all animals with a backbone, whereas Echinodermata consists solely of invertebrates such as sea stars and sea urchins.
Step-by-step explanation:
The phylum that contains both invertebrate and vertebrate groups is Chordata. This phylum is diverse and includes species that range from invertebrates, such as Urochordata (tunicates) and Cephalochordata (lancelets), to vertebrates, which include familiar animals such as mammals, birds, reptiles, amphibians, and fish. The vertebrates are characterized by having a backbone, while the invertebrate chordates are known for possessing the distinctive features of chordates at some point during their lifecycle.
Phylum Echinodermata includes only invertebrates, such as sea stars, sea urchins, and sea cucumbers, which have pentaradial symmetry and a spiny body covering. These echinoderms are exclusively marine organisms with a unique water-based circulatory system and a calcareous endoskeleton made up of ossicles covered by a spiny skin.