Chapter 33

Question 1

Invertebrates

Answer 1

Animals lacking a backbone

Question 2

Invertebrates account for more than _____ of know animal species

Answer 2

95%

Question 3

Example of Porifera

Answer 3

Sponge

Question 4

Example of Acoela

Answer 4

flatworms

Question 5

Example of Ctenophora

Answer 5

Comb Jelly

Question 6

Example of Cnidaria

Answer 6

Jelly

Question 7

Example of Placozoa

Answer 7

Placozoan

Question 8

Animals in the phylum Porifera are known informally as ________

Answer 8

sponges

Question 9

Filter feeders

Answer 9

animals that capture their food particles that are suspended in the water that pass through their body

Question 10

T/F: Sponges lack true tissues and organs

Answer 10

True

Question 11

Cnidarians have diversified into a wide range of both ______ and ______ forms including jellies, corals, and hydras

Answer 11

Sessile; motile

Question 12

The gastrovascular cavity

Answer 12

the main part in the basic body plan of a cnidarian; a sac with a central digestive compartment

Question 13

T/F: Cnidarians have two holes: a mouth and an anus

Answer 13

False; they have one hole that functions as both

Question 14

Two variations of the Cnidarian body plan

Answer 14

A polyp or medusa

Question 15

Polyp

Answer 15

sessile; adheres to the substrate by the aboral end of its body

Question 16

Medusa

Answer 16

has a bell-shaped body with its mouth on the underside

Question 17

The clade Bilateral contains ___________, __________, and ____________

Answer 17

Lophotrochozoa; Ecdysozoa; Deuterostomia

Question 18

Flatworm phylum

Answer 18

Platyhelminthes

Question 19

Planarians

Answer 19

the best-known flatworms

Question 20

Planarians live in __________ and prey on ____________

Answer 20

fresh water; smaller animals

Question 21

T/F: Planarians have eyes

Answer 21

False; they have light-sensitive eyespots

Question 22

Hermaphrodites

Answer 22

organisms that can reproduce sexually, or asexually through fission

Question 23

Mulluscs’ phylum and what it includes

Answer 23

Mollusca; snails, slugs, oysters, clams, octopuses, and squids

Question 24

The three main parts of all molluscs’ body plan

Answer 24

1) Muscular foot
2) Visceral mass
3) Mantle

Question 26

Four major classes of molluscs

Answer 26

1) Polyplacophora (chitons) 2) Gastropoda (snails and slugs) 3) Bivalvia (clams, oysters, and other bivalves) 4) Cephalopoda (squids, octopuses, and cuttlefish)

Question 28

Annelids

Answer 28

Coelomates with bodies composed of a series of fused rings

Question 29

Leeches secrete ________ to prevent blood from coagulating

Answer 29

hirudin

Question 30

Cuticle

Answer 30

the tough coat covering Ecdysozoans

Question 31

The two largest phyla of Exdysozoans

Answer 31

1) nematodes (roundworms) 2) arthropods

Question 32

Arthropod body plan

Answer 32

consists of a segmented body, hard exoskeleton, and jointed appendages (dates back to the Cambrian explosion)

Question 33

Open circulatory system

Answer 33

Hemolymph is circulated into the spaces surrounding the tissue and organs rather than through blood vessels

Question 34

Book lungs

Answer 34

found in spired; allowed for gas exchange

Question 35

Most modern chelicerates are ________, which include...

Answer 35

arachnids; ...spiders, scorpions, ticks, and mites

Question 36

Myriapods include __________ and ___________

Answer 36

millipedes; centipedes

Question 37

T/F: Most living myriapods are terrestrial

Answer 37

False; All are terrestrial

Question 38

Echinoderms include...

Answer 38

sea stars and sea urchins

Question 39

Chordates include...

Answer 39

vertebrates

Question 40

Echinoderm phylum

Answer 40

Echinodermata

Question 41

Chordates phylum

Answer 41

Chordata

Question 42

Echinoderms and chordates constitute the clade _____________

Answer 42

Deuterostomia

Question 43

Deuterostomes share the developmental traits...

Answer 43

Radial cleavage and the formation of the anus from the blastopore

Question 44

Echinoderms

Answer 44

slow-moving or sessile marine animals such as sea stars

Question 45

water vascular system

Answer 45

Shared by echinoderms; a network of hydraulic canals branching into tube feet that function in locomotion and feeding