1- Sponges: bodies of sponges are composed of openings and chambers lined with specific cells containing whip-like flagella. These cells are called choanocytes.
2- Cnidarians: cnidarians have specific cells (cnidocytes) that fire harpoon-like stings that protect the animals or are used to capture prey.
3- Platyhelminthes: flatworms are composed of three layers of cells (endoderm, ectoderm, and mesoderm) but lack an internal body cavity.
4- Nematoda: the body of roundworms is elongated but is not segmented/
5- Annelida: the body of Annelida is elongated and segmented while each segment has the same set of organs.
6- Mollusks: all mollusks have a specific body structure called a mantle. This mantle contains a cavity providing breathing and excretion.
7- Arthropods: all arthropods have segmented bodies and joined limbs.
8- Echinoderms: adult forms of Echinodermata have radial symmetry while larval forms are bilateral.