| 5212402068 | Two early-diverging groups of animals | Sponges and cnidarians | | 0 |
| 5212410939 | Animals in the phylum _________ are known informally as ________. | Porifera, sponges | | 1 |
| 5212413154 | Filter feeders | Capturing food particles suspended in the water that passes through their body; Characteristic of sponges. | | 2 |
| 5212430530 | Tissues | Groups of cells that function as a unit; what sponges lack | | 3 |
| 5212434936 | Choanocytes | Flagellated collar cells | | 4 |
| 5212437504 | Amoebocytes | Mobile collar cells that play roles in digestion and structure. | | 5 |
| 5212449230 | Diversification of cnidarians | Wide range of both sessile and motile forms including hydrozoans, jellies, and sea anemones | | 6 |
| 5212460437 | Polyp | Sessile form | | 7 |
| 5212462314 | Medusa | Motile form | | 8 |
| 5212466472 | Gastrovascular cavity | Sac with a central digestive compartment; basic body plan of a cnidarian | | 9 |
| 5212476161 | Diet of cnidarians | Carnivores that use tentacles to capture prey | | 10 |
| 5212480669 | Do cnidarians have a brain? | No, but instead have a noncentralized nerve net associated with sensory structures distributed throughout the body | | 11 |
| 5212485890 | Cambrian explosion | Earliest fossil appearance of many major group of living animals | | 12 |
| 5212509457 | Bilaterians | A clade whose members have a complete digestive tract and a bilaterally symmetric form; makes up most fossils of the Cambrian period | | 13 |
| 5212523832 | Body plan | A set of morphological and developmental traits | | 14 |
| 5212538623 | Three important aspects of animal body plans | Symmetry, tissues, and body cavities | | 15 |
| 5212542592 | Radial symmetry | No front and back or left and right; often drifting or weakly swimming | | 16 |
| 5212551798 | Bilateral symmery | Two-sided symmetry | | 17 |
| 5212561558 | Characteristics of bilaterally symmetrical animals | Dorsal and ventral side, left and right side, anterior and posterior ends, and sensory equipment concentrated in the anterior end | | 18 |
| 5212583353 | Ectoderm | Germ layer covering the embryo's surface | | 19 |
| 5212585297 | Endoderm | Innermost germ layer and lines the developing digestive tube, called the archenteron | | 20 |
| 5212589296 | Mesoderm | A third germ layer that fills the space between the ectoderm and the ectoderm in all bilaterally symmetric animals. | | 21 |
| 5212598346 | Body cavity | Fluid or air-filled space between the digestive tract and the outer body wall; Common in most bilaterians. | | 22 |
| 5212610804 | What does the body cavity do? | Cushion suspended organs, act as a hydrostatic skeleton, and enable internal organs to move independently of the body wall | | 23 |
| 5212628070 | Phylogenies now combine molecular data with morphological data reflecting: | 1. All animals share a common ancestor
2. Sponges are basal animals
3. Eumetazoa is a clade of animals (eumetazoans) with true tissues
4. Most animal phyla belong to the clade Bilateria
5. Most animals are invertebrates with chordata phylum being the exception | | 24 |
| 5212654976 | Clades of bilaterians | Lophotrochozoa, Ecdysozoa, and Deuterostomia | | 25 |
| 5212663401 | Arthropods | Most numerous species; insects are the most diverse | | 26 |
| 5212670488 | Exoskeleton | Arthropod body plan that's made of layers of protein and the polysaccharide chitin | | 27 |
| 5212676722 | Function of exoskeleton | Provides structural support and protection from physical harm and desiccation | | 28 |
| 5212686154 | Chordates | bilaterian animals that belong to the clade of animals known as Deuterostomia | | 29 |
| 5212692254 | Four key derived characters of chordates | Notochord, dorsal and hollow nerve cord, Pharyngeal slits, and a muscular, post-anal tail | | 30 |
| 5212708584 | Notochord | A flexible rod providing support | | 31 |
| 5212710832 | Pharyngeal slits | Function in filter feeding, as gills, or as parts of the head | | 32 |
| 5212747004 | Lancelets | Basal group of extant, blade-shaped animals that closely resemble the idealized chordate | | 33 |
| 5212753499 | Earliest vertebrates | Soft-bodied, jawless animals that hunted prey using a set of barbed hooks in their mouth | | 34 |
| 5212760952 | Only two extant lineages of jawless fish | Hagfishes and lampreys | | 35 |
| 5212763665 | Gnathostomes | Jawed vertebrates; outnumber jawless vertebrates today | | 36 |
| 5212771850 | Gnathostomes lineages | Chondrichthyans, ray-finned fishes, and lobe-fins | | 37 |
| 5212778661 | Humans and other terrestrial animals | are derived from lobe-fins | | 38 |
| 5212780634 | Chondichthyans | sharks, rays, and their relatives; skeletons are composed primarily of cartilage | | 39 |
| 5212789335 | Ray-finned fishes | Include nearly all the familiar aquatic osteichthyans | | 40 |
| 5212795438 | Osteichthyans | have a bony endoskeleton | | 41 |
| 5212797386 | Lobe-fins | Other major lineage of osteichthyans | | 42 |
| 5212803231 | Key derived trait in the lobe-fins | is the presence of rod-shaped bones surrounded by a thick layer muscle in their pectoral and pelvic fins | | 43 |
| 5212813393 | Three lineages of lobe-fins that survive | Coelacanths, lungfishes, and tetrapods | | 44 |
| 5212816387 | Tetrapods | Terrestrial vertebrates with limbs and digits | | 45 |
| 5212834392 | Amphibians | Include salsmanders, frogs, and caecilians; Restricted to moist areas within their terrestrial habits | | 46 |
| 5212839829 | Amniotes | a group of tetrapods whose living members are the reptiles, including birds, and mammals | | 47 |
| 5212849369 | Amniotic egg | Contains membranes that protect the embryo; led to less dependence on an aquatic environment | | 48 |
| 5212853065 | Reptiles | One of two living lineages of amniotes | | 49 |
| 5212859750 | Reptile clade members | Lizards, snakes, turtles, crocodilians, and birds | | 50 |
| 5212866703 | Characteristics of reptiles | Have scales that create a waterproof barrier, lay shelled eggs on land, mostly ectothermic; birds are endothermic | | 51 |
| 5212876585 | Ectothermic | Absorbing external heat as the main source of body heat | | 52 |
| 5212879402 | Endothermic | Capable of keeping the body warm through metabolism | | 53 |
| 5212885766 | Where do mammals fit in phylogeny? | Other extant lineage of amniotes | | 54 |
| 5212889859 | Distinctive traits of mammals | Mammary glands that produce milk, hair, differentiated teeth | | 55 |
| 5212901264 | Three living lineages of mammals | monotremes, marsupials, and eutherians | | 56 |
| 5212923590 | Human classification | Primates, nestled within ape group | | 57 |
| 5212924955 | Characteristics of humans | Upriht posture, bipedal locomotion, larger brains capable of language, symbolic thought, artistic expression, and the use of complex tools. | | 58 |
