| A | B |
|---|
| do not have a notocord or vertebrae | Invertebrates |
| have a notocord, sometimes with vertebrae | Vertebrates |
| *not* a characteristic of animals | autotrophic (makes its own food) |
| tissues that develop from the endoderm | digestive system |
| mesoderm-lined body cavity found in some invertebrates | coelom |
| the first known animals (organism) to show bilateral symmetry | Platyhelminthes (flatworms) |
| external skeleton | exoskeleton |
| first segmented animals | Annelids (example: earth worms) |
| ectoderm | outer layer of cells that develop into skin and body coverings, and gave rise to the nervous system |
| Cambrian Explosion | gave rise to many different kinds of animals |
| body plan | way in which organs & tissues are organized to produce animals |
| common ancestors of all multi-cellular organisms had this | 2 distinct cell layers separated by a middle jelly layer |
| segments | body compartments that repeat parts of an animal |
| increase body size of animal, and eventually evolved into different organs | segments |
| cephalization | an animal who has developed a front end enough to be called a head |
| bilateral symmetry | animals with left and right sides that are identical |
| examples of mollusks | clams, snails, squid, octopus, nautilus, cuttlefish, slugs |
| skeleton located within the body | endoskeleton |
| radial symmetry | body parts that repeat around the center of an organism |
| example of organism with radial symmetry | jellyfish, hydra, starfish, squid, octopus, sand dollar |
| example of organisms with no symmetry | sponge |
| open circulatory system | blood from the heart is not entirely contained in blood vessels |
| closed circulatory system | blood is contained inside blood vessels which passes through parts of the body and back to the heart again |
| extracellular digestion | digestion takes place outside the cells |
| intracellular digestion | digestion takes place inside the cell |
| digested products are absorbed into blood vessles | extracellular digestion |
| sponges digest this way | intracellular digestion |
| all invertebrates are capable of this | sexual reproduction |
| 3 types of body plans | asymmetry, radial, and bilateral |
| radula | Mollusks (gastropods) have a tongue-like organ with rows of teeth - allows them to scrape algae off a surface |
| coelom | a body cavity that holds a digestive cavity or organs; prevents squeezing or twisting of internal cavity/organs by body movement |
| hydrostatic skeleton | use a water filled cavity for movement |
| 7 functions all invertebrates need to do to be able to survive | Support/movement; Feeding & digestion; Internal transport; Respiration; Excretion; Response; Reproduction |
| hermaphrodite | organism who has both female and male sexual reproductive organs |
| mesoderm | middle layer of cells that develop into skeleton and muscles |
| endoderm | inner layer of cells that develop into the tissues and organs of the digestive tract |
| Phylum Porifera | No symmetry; 2 layers of cells (endoderm and ectoderm with jelly layer in between); spicules (endoskeleton); reproduce asexually and sexually; some are hermaphroditic |
| Phylum Cnidaria | Radial symmetry; 2 layers of cells (endoderm and ectoderm with jelly layer in between); hydroskeleton; reproduce asexually (polyps) and sexually (medusae); have stinging cells on tentacles – shoot out nematocytes |
| Phylum Platyhelminthese | bilateral symmetry; show cephalization; 3 cell layers - endoderm, ectoderm and mesoderm; Acoelomate – doesn’t have a body cavity; Asexual – regeneration and sexual (hermaphroditic); some are parasitic |
| Phylum Nematoda | bilateral symmetry; show cephalization; 3 cell layers - endoderm, ectoderm and mesoderm; Pseudocoelom - false body cavity; No asexual reproduction; sexual (hermaphroditic); most are parasitic |
| Phylum Mollusca | bilateral symmetry; 3 cell layers (endo-, ecto- and mesoderm) & ceolom; Bivalves - 2 shells, Gastropods - 1 shell, Cephalopods - no shell; sexual (hermaphroditic & distinct sexes) |
| Phylum Annelida | bilateral symmetry; 3 cell layers (endo-, ecto- and mesoderm) & coelom; closed circulatory system; Asexual – regeneration; sexual (hermaphroditic or distinct sexes) |
| Phylum Echinodermata | radial symmetry; 3 cell layers (endo-, ecto- and mesoderm); endoskeleton; closed circulatory system; Asexual – regeneration; Sexual - separate sexes (a few are hermaphroditic) |
| Phylum Arthropoda | bilateral symmetry; 3 cell layers (endo-, ecto- and mesoderm); exoskeleton; jointed appendages; head, thorax, abdomen; Sexual - separate sexes; can molt |
| examples of Annelids | segmented worms (earth worms), leeches |
| examples of Arthropods | flies, bees, butterflies, mosquitos, spiders, crustaceans (crabs, lobsters, shrimp) |
| examples of Echidoderms | starfish, sea urchin, sand dollar |
| examples of Mollusks | clam, oyster, octopus, squid, snail |
| examples of Nematodes | roundworms, hookworms, pinworms |
| examples of Platyhelminthese | Planaria (flatworms), flukes, tapeworms |
| examples of Cnidaria | jellyfish, coral, sea anemone, hydra |
| example of Porifera | sponge |
