Campbell Biology 10th Ed: Chapter 33 (An Introduction to Invertebrates

Question 0

What percentage of known animal species are invertebrates?

Answer 0

95%

Question 1

invertebrates

Answer 1

animals that lack a backbone

Question 2

What animals are known to be morphologically diverse and occupying almost every habitat on Earth?

Answer 2

invertebrates

Question 3

Sponges are ____ animals that lack ____ tissues

Answer 3

basal; true

Question 4

What phyla are known as sponges?

Answer 4

Porifera

Question 5

How do animals in the phylum Porifera move?

Answer 5

they are sedentary

Question 6

Where do sponges live?

Answer 6

in marine or fresh water

Question 7

How do sponges feed?

Answer 7

filter feed

Question 8

filter feeders

Answer 8

capture food particles suspended in water that passes through their body

Question 9

Water is drawn through pores into a cavity called the ______ and out through and opening called the ______

Answer 9

spongocoel; osculum

Question 10

What do sponges lack?

Answer 10

true tissues and organs

Question 11

Sponge diagram

Answer 11

Question 12

Eumetazoa

Answer 12

animals with true tissues

Question 13

cnidarians

Answer 13

ancient carnivorous phylum of eumetazoans, 580MYA-present. Cnidarians are classified into four main groups: the almost wholly sessile Anthozoa (sea anemones, corals, sea pens); swimming Scyphozoa (jellyfish); Cubozoa (box jellies); and Hydrozoa, a diverse group that includes all the freshwater cnidarians as well as many marine forms, and has both sessile members, such as Hydra, and colonial swimmers, such as the Portuguese Man o’ War.

Question 14

What two variations exist of the cnidarian body plan?

Answer 14

the sessile polyp and motile medusa

Question 15

polyp

Answer 15

sessile cnidarian that adheres to the substrate by the aboral end of its body

Question 16

medusa

Answer 16

motile cnidarian that has a bell shaped body with a mouth on its underside

Question 17

cnidarian body plans

Answer 17

Polyp and medusa forms of cnidarians. The body wall of a cnidarian has two layers of cells: an outer layer of epidermis (darker blue; derived from ectoderm) and an inner layer of gastrodermis (yellow; derived from endoderm). Digestion begins in the gastrovascular cavity and is completed inside food vacuoles in the gastrodermal cells. Sandwiched between the epidermis and gastrodermis is a gelatinous layer, the mesoglea.

Question 18

What do cnidarians use to capture prey?

Answer 18

tentacles

Question 19

cnidocytes

Answer 19

unique cells on cnidarian tentacles that are used for defense and capture of prey

Question 20

nematocysts

Answer 20

specialized organelles in cnidocytes that eject a stinging thread

Question 21

cnidocyte diagram

Answer 21

A cnidocyte of a hydra. This type of cnidocyte contains a stinging capsule, the nematocyst, which contains a coiled thread. When a “trigger” is stimulated by touch or by certain chemicals, the thread shoots out, puncturing and injecting poison into prey.

Question 22

hydrozoans

Answer 22

cnidarians that alternate between polyp and medusa forms

Question 23

hydra

Answer 23

freshwater cnidarian that exists only in polyp form and reproduces asexually by budding

Question 24

hydra life cycles

Answer 24

The life cycle of the hydrozoan Obelia. The polyp is asexual, and the medusa is sexual, releasing eggs and sperm. These two stages alternate, one producing the other.

Question 25

\_\_\_\_\_\_ have the widest range of animal body forms

Answer 25

lophotrochozoans

Question 26

Bilaterian animals have ______ symmetry and ________ development

Answer 26

bilateral; triploblastic

Question 27

What do most bilaterians have?

Answer 27

a coelom and digestive tract with two openings

Question 28

What three clades are within the clade Bilateria?

Answer 28

Lophotrochozoa, Ecdysozoa, and Deuterostomia

Question 29

flatworms

Answer 29

members of the phylum platyhelminthes that live in marine, freshwater, and damp terrestrial habitats

Question 30

How many germ layers do flatworms have?

Answer 30

three

Question 31

What is the nature of flatworms' coeloms

Answer 31

acoelomates

Question 32

How many openings do flatworms' gastrovascular cavities have?

Answer 32

one

Question 33

Where does gas exchange happen on flatworms?

Answer 33

on their surface

Question 34

protonephridia

Answer 34

regulate osmotic balance in flatworms As illustrated in Figure 44.9, the excretory systems of flatworms (phylum Platyhelminthes) consist of units called protonephridia (singular, protonephridium), which form a network of dead-end tubules. The tubules, which are connected to external openings, branch throughout the flatworm body, which lacks a coelom (body cavity). Cellular units called flame bulbs cap the branches of each protonephridium.

Question 35

Why are flatworms dorsoventrally flattened shaped?

Answer 35

it maximizes their surface area for gas exchange

Question 36

flatworm diagram

Answer 36

Anatomy of a planarian.

Question 37

trematodes

Answer 37

parasitic platyhelminthes that have complex life cycles with alternating sexual and asexual stages

Question 38

Trematodes that parasitize humans spend part of their lives in ____ hosts?

Answer 38

snail

Question 39

How to trematodes parasitize?

Answer 39

they produces surface proteins that mimic their host and release molecules that manipulate the host's immune system

Question 40

trematode life cycle

Answer 40

The life cycle of a blood fluke (*Schistosoma* *mansoni*), a trematode.

Question 41

tapeworms

Answer 41

parasites of vertebrates that lack digestive systems

Question 42

How do tapeworms "feed"?

Answer 42

they absorb nutrients from their host's intestine

Question 43

tapeworm diagram

Answer 43

Anatomy of a tapeworm. The inset shows a close-up of the scolex (colorized SEM)

Question 44

ectoprocts

Answer 44

sessile colonial animals that superficially resemble plants

Question 45

bryozoans

Answer 45

alternate name for ectoprocts

Question 46

What are ectoproct exoskeletons like?

Answer 46

they encase the entire colony

Question 47

Three main parts of a mollusc's body plan?

Answer 47

muscular foot, visceral mass, and mantle

Question 48

Many molluscs have a water filled ____ \_\_\_\_\_

Answer 48

mantle cavity

Question 49

How to molluscs feed?

Answer 49

using the radula

Question 50

molluscs diagram

Answer 50

Question 51

Which molluscs are hermaphrodites?

Answer 51

snails

Question 52

Where are the gonads located in molluscs?

Answer 52

the visceral mass

Question 53

The life cycle of many molluscs includes a ciliated larval stage called a \_\_\_\_\_\_\_

Answer 53

trochophore

Question 54

What do earthworms eat?

Answer 54

soil

Question 55

How to earthworms get nutrients?

Answer 55

they extract nutrients from soil as it moves through their alimentary canal

Question 56

alimentary canal

Answer 56

digestive tube that extends from the mouth to the anus

Question 57

Are earthworms hermaphrodites?

Answer 57

yes

Question 58

Do earthworms crossfertilize?

Answer 58

yes

Question 59

How do earthworms reproduce asexually?

Answer 59

by fragmentation

Question 60

earthworm anatomy

Answer 60

Anatomy of an earthworm, a sedentarian

Question 61

What are the six pairs of arachnid appendages?

Answer 61

celicerae, pedipalps, and four pairs of walking legs

Question 62

book lungs

Answer 62

respiratory organs in spiders where gas exchange occurs

Question 63

Many spiders produce \_\_\_\_\_

Answer 63

silk

Question 64

What is spider silk?

Answer 64

a liquid protein from specialized abdominal glands

Question 65

arachnid anatomy

Answer 65

Question 66

What is clade Hexapoda comprised of?

Answer 66

insects and their relatives

Question 67

Where do insects live?

Answer 67

in almost every terrestrial habitat and in fresh water

Question 68

The internal anatomy of an insect includes?

Answer 68

several complex organ systems

Question 69

insect anatomy

Answer 69

Anatomy of a grasshopper, an insect. The insect body has three regions: head, thorax, and abdomen. The segmentation of the thorax and abdomen is obvious, but the segments that form the head are fused.

Question 70

echinoderms

Answer 70

slow moving or sessile marine animals

Question 71

Example of echinoderms?

Answer 71

sea stars

Question 72

What is the outer surface of an echinoderm like?

Answer 72

a thin epidermis covering an endoskeleton of hard calcareous plates

Question 73

What system is unique to echinoderms?

Answer 73

water vascular system

Question 74

water vascular system

Answer 74

a network of hydraulic canals branching into tube feet that is used for locomotion, feeding, waste disposal, and respiration

Question 75

tube feet

Answer 75

tubular projections on the surface of echinoderms that are a part of the water vascular system

Question 76

How does gender work in most echinoderms?

Answer 76

Males and females are usually separate

Question 77

How do echinoderms reproduce?

Answer 77

external sexual reproduction

Question 78

sea star anatomy

Answer 78