Terms : Hide Images
| 2436565487 | blastula | Embryonic stage in most animals consisting of a single layer of cells surrounding a hollow cavity | 0 | |
| 2436565488 | gastrula | Embryonic stage following the blastula that has an inner and outer cell layer | 1 | |
| 2436565489 | larva | Immature form of an animal that looks different from the adult form | 2 | |
| 2436565490 | metamorphosis | Complete change of body form in some animals from a larva to an adult | 3 | |
| 2436565491 | invertebrate | Member of a group of animals without a backbone | 4 | |
| 2436565492 | vertebrate | Animal with a backbone | 5 | |
| 2436565493 | sponge | Member of a group of animals that lack true tissues and organs | 6 | |
| 2436565494 | collar cell | Flagellated cell in a sponge's inner layer | 7 | |
| 2436565495 | amoebocyte | Cell found in sponges and other animals that may digest and distribute food, dispose of wastes, and change into other cell types | 8 | |
| 2436565496 | sessile | Anchored in place | 9 | |
| 2436565497 | cnidarian | Member of a group of invertebrates with radial symmetry and tentacles with stinging cells | 10 | |
| 2436565498 | radial symmetry | Body plan in which an organism can be divided into equal parts around a central axis | 11 | |
| 2436565499 | cnidocyte | Specialized cell in cnidarians that functions in defense and capturing prey | 12 | |
| 2436565500 | nematocyst | Stinging capsule found in a cnidocyte | 13 | |
| 2436565501 | gastrovascular cavity | Digestive sac | 14 | |
| 2436565502 | polyp | Cnidarian body form consisting of a cylindrical body with tentacles radiating from one end | 15 | |
| 2436565503 | medusa | Cnidarian body form that is umbrella-shaped with fringes of tentacles | 16 | |
| 2436565504 | flatworm | Member of a group of small, leaflike or ribbonlike invertebrates that includes planarians | 17 | |
| 2436565505 | bilateral symmetry | Body plan in which an animal can be divided into two equal sides | 18 | |
| 2436565506 | roundworm | Member of a group of cylindrical invertebrates with pointed heads and tapered tails | 19 | |
| 2436565507 | complete digestive tract | Continuous digestive tube with a separate mouth and anus | 20 | |
| 2436565508 | rotifer | Member of a group of invertebrates with a complete digestive tract and a crown of rotating cilia | 21 | |
| 2436565509 | annelid | Segmented worm | 22 | |
| 2436565510 | closed circulatory system | Blood transport system in which blood remains enclosed in vessels, and nutrients, oxygen, and wastes diffuse through vessel walls | 23 | |
| 2436565511 | acoelomate | Animal lacking a body cavity | 24 | |
| 2436565512 | pseudocoelom | Fluid-filled internal space that is in direct contact with the wall of the digestive tract | 25 | |
| 2436565513 | coelom | Fluid-filled body cavity completely lined by a layer of mesoderm cells | 26 | |
| 2436565514 | mollusk | Member of a group of invertebrates characterized by a muscular foot and a mantle | 27 | |
| 2436565515 | mantle | Body surface outgrowth that drapes over a mollusk | 28 | |
| 2436565516 | radula | Scraping organ characteristic of mollusks | 29 | |
| 2436565517 | open circulatory system | Blood transport system in which blood is pumped into chambers where it comes in direct contact with tissues and organs | 30 | |
| 2436565518 | gastropod | Member of a group of mollusks that includes snails and slugs | 31 | |
| 2436565519 | bivalve | Member of a group of mollusks with hinged shells, such as clams, mussels, scallops, and oysters | 32 | |
| 2436565520 | cephalopod | Member of a group of mollusks that includes squids and octopuses | 33 | |
| 2436565521 | echinoderm | Member of a group of marine invertebrates that includes sea urchins and sea stars | 34 | |
| 2436565522 | endoskeleton | Skeleton located inside the body; characteristic of all vertebrates and some invertebrates | 35 | |
| 2436565523 | water vascular system | In echinoderms, a network of water-filled canals that function in movement, food gathering, and as a basic circulatory system | 36 | |
| 2436565524 | tube feet | In echinoderms, structures that are part of the water vascular system and function in locomotion, feeding, and gas exchange | 37 |
