Biology 1407 Test 3

Question 1

invertebrate

Answer 1

animal that does not have a backbone

Question 2

animals

Answer 2

multicelled heterotrophs with unwalled cells; are motile during part or all of the life cycle

Question 3

bilateral symmetry

Answer 3

right and left halves are mirror images

Question 4

cephalization

Answer 4

concentration of nerve and sensory cells at the head end

Question 5

coelom

Answer 5

a body cavity that surrounds the gut and is lines with tissue derived from the mesoderm

Question 6

deuterostomes

Answer 6

lineage of bilateral animals in which the seconds opening on the embryo surface develops into a mouth

Question 7

gut

Answer 7

a sac or tube in which food is digested

Question 8

protostomes

Answer 8

lineage of bilateral animals in whihc the first opening on the embryo surface develops into a mouth

Question 9

pseudocoelom

Answer 9

incompletely lines body cavity of some animals

Question 10

radial symmetry

Answer 10

having parts arranged around a central axis, like spokes around a wheel. a cut down the middle of any plane produces two symmetrical halves

Question 11

hermaphrodite

Answer 11

animal that produces both egs and sperm, either simultaneously or at different times in its life.

Question 12

larva

Answer 12

in some animal life cycles, an immature form that hasa different body structure than an adult

Question 13

sessile animal

Answer 13

animal that lives fixed in place on some surfaces

Question 14

sponge

Answer 14

aquatic invertebrate that has no body symmetry, tissues, or organs; feeds by filtering food from the water

Question 15

cnidarian

Answer 15

radially symmetrical invertebrate that has tentacles with stinging cells (cnidocytes)

Question 16

cnidocyte

Answer 16

stinging cell unique to cnidarians

Question 17

gastrovascular cavity

Answer 17

saclike cavity that functions in digestion and gas exchange in cnidarians and flatworms

Question 18

hydrostatic skeleton

Answer 18

of soft bodied invertebrates, a fluid-filled chamber that muscles exert force against, redistributing the fluid

Question 19

medusa

Answer 19

bell like cnidarian body fringes with tentacles

Question 20

nerve net

Answer 20

mesh of neve cells with no central control organ

Question 21

polyp

Answer 21

pillarlike cnidarian body topped with tentacles; sessile

Question 22

flatworm

Answer 22

acoelomate, unsegmented worm; for example, a planarian or tapeworm

Question 23

ganglion

Answer 23

cluster of nerve cell bodies

Question 24

nerve cord

Answer 24

bundle of nerve fibers that runs the length of the body in many invertebrates

Question 25

pharynx

Answer 25

tube connecting the mouth to the digestive tract

Question 26

annelid

Answer 26

segmented worm with a coelom, complete digestive system and closed circulatory system

Question 27

nephridium

Answer 27

of annelids and some other invertebrates, one of many water-regulating units that help control the content and volume of tissue fluid

Question 28

trochophore larva

Answer 28

type of ciliated larva that forms during the development of mollusks and some annelids

Question 29

gills

Answer 29

folds or body extensions that increase th surface area for respiration

Question 30

mantle

Answer 30

of mollusks, extension of the body wall

Question 31

mollusk

Answer 31

invertebrate with a reduced coelom and a mantle, including bivalves, gastropods, and cephalopods

Question 32

radula

Answer 32

of many mollusks, a tonguelike organ hardened with chitin that is used in feeding

Question 33

rotifer

Answer 33

tiny bilateral, pseudocoelomate animal with ciliated head

Question 34

tardigrade

Answer 34

a tiny coelomate animal with four pairs of legs; in a dormant state, it can survive extremely adverse conditions

Question 35

roundworm

Answer 35

unsegmented pseudocoelomate worm with a cuticle that is molted periodically as the animal grows

Question 36

antenna

Answer 36

of some arthropods, sensory structure on the head that detects touch and odors

Question 37

arthropod

Answer 37

invertebrate with jointed legs and a hard exoskeleton that is periodically molted; for example, an insect or crustacean

Question 38

exoskeleton

Answer 38

of some invertebrates, hard external parts that muscles attach to move

Question 39

metamorphosis

Answer 39

remodeling of body form during the transition from larva to adult

Question 40

arachnids

Answer 40

land dwelling chelicerate arthropods with four pairs of walking legs; spiders, scorpions, mites and ticks

Question 41

chelicerates

Answer 41

arthropod subgroup with specialized feeding structures (chelicerae) and no antennae

Question 42

myriapod

Answer 42

land dwelling arthropod with two antennae and an elongated body with many segments; a millipede or a centipede

Question 43

crustaceans

Answer 43

mostly marine arthropod group with two pairs of antennae and a calcium-stiffened exoskeleton

Question 44

insect

Answer 44

six legged arthropod with two antennae and two compound eyes. member of the most diverse class of animals

Question 45

malpighian tubule

Answer 45

water conserving excretory organ of insects

Question 46

echinoderms

Answer 46

invertebrates with hardened plates and spines embedded in the skin or body and water-vascular system

Question 47

water-vascular system

Answer 47

of echinoderms, a system of fluid-filled tubes and tube feet that function in locomotion