Chapter 28

Question 1

what characterized clade parazoa?

Answer 1

no tissues, body cavity, or symmetry

Question 2

who are members of phylum porifera and where are they found?

Answer 2

sponges; marine and freshwater

Question 3

are sponges free swimming or sessile?

Answer 3

larvae free swimming, adults sessile

Question 4

list and describe the 3 layers of sponge body walls

Answer 4

1. inner layer: specialized cells, for feeding
2. middle layer: gelatinous, protein rich matrix called mesohyl, may contain spicule or spongin
3. outer layer: protective epithelial cells

Question 5

what is the space inside the sponge called?

Answer 5

spongocoel

Question 6

what are the pores in the outer layer of a sponge called and what do they do?

Answer 6

ostia, let food and water inside

Question 7

list the 3 sponge body types, in order from simplest to most complex and most surface arearelease of gamet

Answer 7

ascenoid, syconoid, leuconoid

Question 8

what is the role of the choanocyte flagella in porifera?

Answer 8

keep wtaer moving for the filter feeding

Question 9

how does sponges reproduce?

Answer 9

asexually: through fragmentation and
sexually: through release of gametes for random mating

Question 10

what do larval sponges use for swimming?

Answer 10

cilia

Question 11

what 2 clades are in eumetazoa?

Answer 11

radiata and bilateria

Question 12

list the symmetry and body cavity of radiata

Answer 12

radial symmetry and no body cavity

Question 13

what 2 phyla are in clade radiata?

Answer 13

cnidaria and ctenophora

Question 14

where are cnidarians found?

Answer 14

nearly all marine

Question 15

do cnidarians have tissues?

Answer 15

yes but no organs

Question 16

discuss the tissue layers of cnidarians

Answer 16

diploblastic, layer of gelatinous material, or mesoglea between endo and ectoderm

Question 17

what is the cnidarian diet?

Answer 17

carnivorous

Question 18

what are the 2 basic body forms of cnidarians?

Answer 18

medusa and polyp

Question 19

how do polyps reproduce?

Answer 19

either sexually or asexually by budding

Question 20

how do medusae reproduce?

Answer 20

sexually, making free swimming larvae called planulae

Question 21

how does digestion work in cnidarians?

Answer 21

internal extracellular digestion; enzymes are released to break down food, then extracellular fragmentation in the gastrovascular cavity, followed by phagocytosis and intracellular digestion

Question 22

how is circulation, respiration, and excretion accomplished in cnidarians?

Answer 22

through diffusion bc no organs

Question 23

what are the unique,specialized cells on the epidermis of cnidarians?

Answer 23

cnidocytes

Question 24

what are the specialized stinging cnidocytes?

Answer 24

nematocysts function in food acquisition and defense

Question 25

list the 4 classes of cnidarians

Answer 25

1. hydrozoa 2. scyphozoa 3. anthozoa 4. cubozoa

Question 26

what is the only class of cnidarians with both marine and freshwater species?

Answer 26

hydrozoa

Question 27

what form of hydrozoa is the portugese man of war?

Answer 27

colonial

Question 28

why are anthozoas only found in shallow water?

Answer 28

because of the symbiotic relationship with the photosynthetic algae in their tissues

Question 29

what do anthozoas secrete?

Answer 29

reef building calcium carbonate

Question 30

how do anthozoas eat?

Answer 30

strictly carnivorous

Question 31

what other animal do sea anenome have a symbiotic relationship with?

Answer 31

clown fish

Question 32

what are the 2 kinds of platyhelminthes?

Answer 32

``` free living flatworms (Turbellaria) parasitic flatworms (Termatoda and Cestoda) ```

Question 33

describe the digestive aspect of platyhelminthes

Answer 33

incomplete digestive tract in turbellaria, no digestive cavity in trematodes and cestodes

Question 34

do platyhelminthes have an excretory system?

Answer 34

yes, but primitive

Question 35

discuss a hallmark aspect of platyhelminthes nervous systems

Answer 35

eyespots that can sense light and dark

Question 36

how do platyhelminthes move?

Answer 36

ciliated epithelial cells, musculatura

Question 37

how do trematodes and cestodes absorb nutrients without a digestive cavity?

Answer 37

directly through body walls

Question 38

describe the excretory system of platyhelminthes

Answer 38

network of fine tubules, with flame cells

Question 39

discuss the role of flame cells in platyhelminthes

Answer 39

located on the side branches, primary function is water balance, secondary function is excretion

Question 40

how are metabolic wastes excreted in platyhelminthes?

Answer 40

directly into the gut and out through the mouth

Question 41

why do platyhelminthes lack a circulatory system?

Answer 41

not a lot going on, flat enough that diffusion works instead

Question 42

describe the reproductive aspects of platyhelminthes

Answer 42

most monoecious (hermaphroditic), but undergo sexual reproduction, and have the capacity for asexual regeneration

Question 43

what interprets the information from the eyespots of platyhelminthes?

Answer 43

a primitive nerve cord

Question 44

list the 3 classes of platyhelminthes?

Answer 44

1. turbellaria 2. cestoda 3. trematoda

Question 45

what are turbellaria and where are they found?

Answer 45

free living flat worms found in marine, freshwater and terrestrial environments

Question 46

what are trematoda and where are they found and also describe their lifecycle

Answer 46

flukes that live as ecto or endo parasites in the bodies of other animals, have a lfiecycle that involves 2 or more hosts

Question 47

what happens in the definitive host?

Answer 47

where adult form of parasite lives and produces eggs, sexual reproduction, eggs are released into the environment and picked up by the intermediate host

Question 48

what happens in the intermediate host?

Answer 48

where parasites live in larval form and reproduce asexually

Question 49

what is the paratinic host?

Answer 49

the transport host, where no reproduction takes place

Question 50

who are cestoda and where are they found?

Answer 50

tapeworms, live as parasites in the bodies of other animals, mostly in the intestines of vertebrates

Question 51

list and describe the 3 zones of the cestoda body

Answer 51

scolex: attachment organ neck: unsegmented portion proglottids: reproductive sections, each is a complex hermaphroditic unit

Question 52

what is the beef tapeworm?

Answer 52

Teania saginata

Question 53

how do cestoda eggs get into the environment?

Answer 53

the proglottid segments break off and come out through the feces of the direct host

Question 54

how do you break the parasite lifecycle?

Answer 54

treat the intermediate host

Question 55

what is a pseudocoel?

Answer 55

a cavity between the mesoderm and endoderm

Question 56

how does the pseudocoel function?

Answer 56

as a hydrostatic skeleton, against which the animal's muscles can work

Question 57

do pseudocoelomates have a circulatory system? why or why not?

Answer 57

no, the function is performed by the fluids that move within the pseudocoel

Question 58

who are the pseudocoelomates?

Answer 58

phyla rotifera and nematoda

Question 59

who are nematodes? symmetry? segmentation

Answer 59

roundworms, bilateral, unsegmented

Question 60

whatbody plan do nematodes have?

Answer 60

tube within a tube

Question 61

what are nematodes covered with that they must molt in order to grow?

Answer 61

a thick flexible cuticle that serves as oxygen exchange

Question 62

describe the reproductive stuff of nematodes

Answer 62

dioecious, very obvious repro tract

Question 63

what are the piercing organs on nematode mouths?

Answer 63

stylets

Question 64

how does food pass through the mouth of nematodes?

Answer 64

the sucking action of the pharynx

Question 65

what phylum does the canine heartworm belong to?

Answer 65

nematoda

Question 66

what are rotifera?

Answer 66

bilateral unsegmented pseudocoleomates with complex internal organs