Lecture 13

Question 1

what are the classes of the phylum ecinodermata

Answer 1

• crinoidea
• asteroidea
• echinoidea
• ophiuroidea
• holothuroidea

Question 2

which of the classes of echinodermata is not included in the subphylum eleutherozoa

Answer 2

crinoidea

Question 3

what is the key characteristic of the subphylum eleutherozoa

Answer 3

they are free living, not sessile

Question 4

what are asteroids

Answer 4

sea stars and starfish

Question 5

what are ophiuroids

Answer 5

brittle stars and basket stars

Question 6

what are echinoids

Answer 6

sea urchins, heart urchins, and sand dollars

Question 7

what are holothuroids

Answer 7

sea cucumbers

Question 8

what are crinoids

Answer 8

sea lillies and feather stars
sessile

Question 9

where is the mouth of crinoids

Answer 9

the top surface

Question 10

what is the mouth in crinoids

Answer 10

an oral disc surrounded by many feeding arms

Question 11

how is food directed to the mouth of crinoids

Answer 11

cilia

Question 12

where is the anus of crinoids

Answer 12

near the mouth

Question 13

what kind of gut do crinoids have

Answer 13

u shaped

Question 14

what kind of feeders are crinoids

Answer 14

filter

Question 15

crinoids - sessile or free living?

Answer 15

sessile

Question 16

asteroids - sessile or free living

Answer 16

free living

Question 17

ophiuroids - sessile or free living

Answer 17

free living

Question 18

echinoids - sessile or free living

Answer 18

free living

Question 19

holothuroids - sessile or free living

Answer 19

free living

Question 20

what are the surfaces of echinoderms called

Answer 20

• oral surface
• aboral surface

Question 21

what is the oral surface of ecinoderms

Answer 21

the surface with the mouth

Question 22

what is the aboral surface of echinoderms

Answer 22

the surface without the mouth

Question 23

what shape are asteroids

Answer 23

star shaped

Question 24

what shape are ophiuroids

Answer 24

star shaped

Question 25

how do ophiuroids move

Answer 25

whip like arms to walk along ocean floor

Question 26

what shape are echinoids

Answer 26

round or spherical

Question 27

what kind of skin do most echinoderms have

Answer 27

hard skin

Question 28

which class of echinoderms has soft skin instead of the typical hard skin

Answer 28

holothuroidea

Question 29

where do holothuroids live

Answer 29

the sea floow mostly, but some are pelagic (swimming)

Question 30

what shape are holothuroids

Answer 30

elongated, spherical or cylindrical body shape

Question 31

in echinoderms, what is the name of the surface with feet

Answer 31

ambulacral surface

Question 32

what are the unique characters of echinoderms not found in any other phylum

Answer 32

1. secondary radial symmetry 2. a water vascular system 3. pedicellariae 4. an endoskeleton composed of ossicles 5. dermal branchia

Question 33

which of the unique characters of echinoderms found in all classes

Answer 33

- secondary radial symmetry - a water vasvular system - an endoskeleton composed of ossicles

Question 34

what is secondary radial symmetry

Answer 34

can cut through the center 5 ways to obtain similar parts

Question 35

what are ambulacral grooves

Answer 35

bands that extend from the mouth of echinoderms along the body

Question 36

what is the vascular system of echinoderms

Answer 36

- water vascular system - fluid filled canals leading to tube feet

Question 37

what are the functions of the vascular system of echinoderms

Answer 37

locomotion, predation, gas exchange, and excretion

Question 38

what are the parts of the vascular system of echinoderms

Answer 38

- ring canal - radial canals - madreporite - stone canal - polian vesicles - lateral canals - ampulla - tube feet

Question 39

what are radial canals in echinoderms

Answer 39

radiate symmetrically from ring canal and run the length of the "arm"

Question 40

what is the madreporite in echinoderms

Answer 40

perforated plate linking the water vascular system to the outside environment

Question 41

what is the stone canal in echinoderms

Answer 41

reinforced canal (calcium carbonate plates) connecting madreporite to ring canal

Question 42

what are polian vesicles in echinoderms

Answer 42

accessory (storage) fluid structures

Question 43

what are lateral canals in echinoderms

Answer 43

perpendicular branching of the radial canal leading to the tube feet

Question 44

what kind of feet do echinoderms have

Answer 44

tube feet

Question 45

how do tube feet in echinoderms maintain their shape

Answer 45

they have connective tissue in their walls

Question 46

what are pedicellariae in echinoderms

Answer 46

tiny 'jaws' that are present on the surface of asteroids and echinoids

Question 47

what is the function of pedicellariae in echinoderms

Answer 47

keep the surface of the animal clean

Question 48

what is unique about the pedicellariae of echinoids

Answer 48

are often on long stalks and can contain powerful venom

Question 49

what are ossicles

Answer 49

small hardened plates made of calcium carbonate that make up the echinoderm skeleton

Question 50

how are ossicles held together

Answer 50

collagen fibers

Question 51

how are ossicles produced

Answer 51

by cells called sclerocytes in the epidermis

Question 52

in holothuriods, small ossicles are scattered where

Answer 52

throughout the dermis

Question 53

in asteroids, crinoids, and ophiuroids, ossicles fuse to form ...

Answer 53

plates

Question 54

in echinoids, plates are fused to form ...

Answer 54

a test

Question 55

what are dermal branchiae

Answer 55

- aka papulae - projections of the coelomic -- cavity with epidermis lined with peritoneum - skin gills

Question 56

what class of echinoderms has dermal branchiae

Answer 56

only asteroidea

Question 57

what is the function of dermal branchiae

Answer 57

gas exchange and removing wastes from the body

Question 58

dermal branchiae are covered in what on both internal and external surfaces

Answer 58

cilia

Question 59

what is the flow of fluid like due to cilia in dermal branchiae

Answer 59

countercurrent exchange opposite directions

Question 60

what features of tube feet make them suitable respiratory structures

Question 61

what is the chief gas exhange organ of holothuroids

Answer 61

respiratory tree

Question 62

what is the respiratory tree in holothuroids

Answer 62

the gas exchange organ of holothuroids

Question 63

how does the respiratory tree in holothuroids work

Answer 63

1. cloacal miscles contract causing dilation 2. anal sphincter open - water flows in 3. anal sphincter closes and cloaca contracts forcing water into respiratory tree 4. anal sphincter opens and respiratory tree contracts forcing water back out the anus

Question 64

what animal has a commensal or parasitic relationship with sea cucumbers

Answer 64

the pearlfish

Question 65

what defense mechinisms have some sea cucumbers evolved

Answer 65

- anal teeth - ceruvian tubules - evisceration

Question 66

what are ceruvian tubules

Answer 66

structures attached to the respiratory tree that can be discharged long and sticky and can contain toxins

Question 67

when i say that sea cucumbers can do evisceration, what does that mean

Answer 67

a rapid softening of the body wall and explosive release of organs into the water, which scares and distracts predators