invertebrate
vertebrate
blastula
anus
radial symmetry
bilateral symmetry
cephalization
cnidocytes
nematocyst
polyp
medusa
internal fertilization
external fertilization
gastrovascular cavity
hydrostatic skeleton
pharynx
ganglia
eyespot
group of cells that can detect changes in the amount of light in the environment
hermaphrodite
individual that has both male and female reproductive organs
septa
crop
gizzard
closed circulatory system
nephridia
gill
filamentous organ in aquatic animals specialized for the exchange of gasses with water
open circulatory system
foot
visceral mass
mantle
exoskeleton
appendage
cephalothorax
region of a crustacean formed by the fusion of the head with the thorax
thorax
abdomen
carapace
mandible
endoskeleton
water vascular system