Chapter 17 Flashcards
Amniotes
Member of a clade of tetrapods that has an amniotic egg containing specialized membranes that protect the embryo. Mammals reptiles and birds.
Amniotic Egg
A shelled egg in which an embryo develops within a fluid filled amniotic sac and is nourished by yolk.
Amphibians
Member of a class of vertebrate animals that includes frogs and salamanders.
Animals
A eukaryotic, multicellular, heterotrophic organism that obtains nutrients by ingestion.
Annelids
A segmented worm.
Anthropoid
A member of the primate group made up of the apes, monkeys and all humans.
Arachnids
A member of a major arthropod group that includes spiders, scorpions, ticks and mites.
Arthropods
A member of the most diverse phylum, includes horseshoe crab, arachnids, crustaceans, millipedes, centipedes and insects. Characterized by chitinous exoskeleton, molting, jointed appendages, and a body formed of distinct segments.
Bilateral Symmetry
An arrangement of body parts such that an organism can be divided equally by a single cut passing longitudinally through it. A mirror image organism.
Birds
Member of a group of reptiles with feathers and adaptations for flight.
Bivalves
A member of a group of molluscs that includes clams, mussels, scallops and oysters.
Blastula
An embryonic stage that marks the end of cleavage during animal development, a hollow ball of cells in many species.
Body cavity
A fluid filled space separating the digestive tract from the outer body wall.
Body Segmentation
Subdivision of an animal’s body into a series of repeated parts called segments.
Bony Fishes
A fish that has a stiff skeleton reinforced by calcium salts.
Cartilaginous Fishes
A fish that has a flexible skeleton made of cartilage.
Centipedes
A carnivorous terrestrial arthropod that has one pair of long legs for each of its numerous body segments, with the front pair modified as poison claws.
Cephalopods
A member of a group of molluscs that includes squids and octopuses.
Chordates
An animal that at some point during its development has a dorsal, hollow nerve chord, a notochord, pharyngeal slits, and a post anal tail. Lancelets, tunicates and vertebrates.
Placenta
In most mammals, the organ that provides nutrients and oxygen to the embryo and helps dispose of its metabolic wastes.
Placental Mammals
Mammal whose young complete their embryonic development in the uterus, nourished via the mother’s blood vessels in the placenta.
Polychaetes
A type of annelid or segmented worm, that typically lives on the seafloor.
Polyp
One of two types of cnidarian body forms; a sessile, columnar, hydra-like body.
Post- anal Tail
A tail posterior to the anus, found in chordate embryos and most adult chordates.
Primates
Member of the mammalian group that includes lorises, pottos, lemurs, tarsiers, monkeys, apes and humans.
Insects
a small arthropod animal that has six legs and generally one or two pairs of wings.
Invertebrates
an animal lacking a backbone
Lancelets
a small elongated marine invertebrate that resembles a fish but lacks jaws and obvious sense organs.
Larva
the active immature form of an insect, especially one that differs greatly from the adult and forms the stage between egg and pupa, e.g., a caterpillar or grub.