Arthropods
Arthropods must do this in order to grow
Molt
Echinoderms exhibit this type of symmetry
Pentaradial
This shared feature of chordates becomes the spinal cord in vertebrates
Dorsal hollow nerve cord
Fish are broadly divided into these two groups
Jawless fish (Agnatha) and Jawed fish (Gnathostomes)
Amphibians go through this developmental process, which is unique among vertebrates
Metamorphosis
This carbohydrate makes up the exoskeleton of arthropods
Chitin
Water vascular system
This flexible, rod-shaped structure becomes the vertebrae in vertebrates
Notochord
This class of fish features sharks, skates, and rays
Chondrichthyes (Cartilaginous Fish)
Amphibians are reliant on water for these two reasons
Need moist skin for respiration and need water to lay eggs in
This key feature that distinguishes arthropods is found in the phylum's name
Jointed appendages
This echinoderm class features hard tests
Echinoidea (urchins and sand dollars)
This shared feature of chordates becomes part of the ears and tonsils in tetrapods
Pharyngeal gill slits
This class of fish features a bony skeleton and most species have overlapping scales
Osteichthyes (Bony Fishes)
About 88% of amphibians are part of this class
Anura (frogs and toads)
This subphylum contains arachnids and horseshoe crabs and in named for their mouth parts
Chelicerata
Unlike in sea stars, all of the internal organs of brittle stars are located here
Central disk
These chordates are filter feeders that bury themselves in the sand
Lancelets
This class of fish is unique among vertebrates because it does not have a vertebral column
Hagfish
This class of amphibians underwent an evolutionary reversal
Apoda (caecilians)
This subphylum contains centipedes and millipedes and is named for their many legs
Myriapoda
These structures form the exoskeleton of many echinoderms
Ossicles
This unique chordate loses many of the chordata characteristics as an adult and resembles coral
Tunicate
This feature of both bony fish and sharks allows them to detect vibrations in the water
Lateral line system
This defense mechanism can allow salamanders to distract and escape predators
Tail autonomy