| A | B |
|---|
| Heterotrophs | organism that obtains nutrients by eating food |
| Invertebrates | animals without an endoskeleton |
| Symmetry | balanced arrangement of body parts |
| Radial Symmetry | more than one line of symmetry |
| Bilateral Symmetry | body divided lengthwise into two equal sides |
| Asymmetrical | lacking symmetry |
| Phylum Porifera | sponges |
| Sponges | simple invertebrates with pores |
| Pore | small opening |
| Non-Mobile | does not move freely, is attached to rocks in ocean |
| Ectoderm | outer body layer |
| Endoderm | inner body layer |
| Regeneration | asexual reproduction, piece breaks off to form new sponge |
| Budding | asexual reproduction, bud forms off side of sponge and develops into new sponge |
| Sexual reproduction | sponge produces sex cells which join and develop into new sponges |
| Phylum Cnidaria | jellyfish, hydra, coral, sea anemones |
| Cnidocytes | stinging cells |
| Polyp | cuplike early stage where organism is attached to surface, mouth facing up |
| Medusa | floating later stage where mouth points down |
| Mesoderm | middle layer where organs develop from |
| Flatworms | simplest worms, have three body layers and flat bodies |
| Tapeworms | parasitic flatworm that holds on to host intestines with hooks and suckers, absorb food digested by host |
| Planarian | free living flatworm with eyespots to sense light |
| Hermaphrodites | organisms with male and female reproductive parts that reproduce by exchanging sperm |
| Roundworms | worms with long bodies and pointed ends (Ascaris_ |
| Hookworms | roundworm that feeds on human blood |
| Segmented worms | most complex worms that have bodies divided into sections (Annelids_ |
| Annelid | "little rings" |
| Leeches | parasitic annelid |
| Earthworms | annelid that makes soil good for growing plants by aerating and loosening the soil, fertilize it with their wastes |
| Mollusks | soft bodied animals |
| Muscular foot | moves organism from place to place |
