echinodermata

Question 1

3 phyla of deuterostomia

Answer 1

echinodermata
hemichordata
chordata

Question 2

share developmental features in deuterostomes

Answer 2

blastopore => anus

radial, indeterminate cleavage. eucoelom via enterocoely

Question 3

synapomorphies of deuterostomia

Answer 3

pharyngeal slits

- three part body coelom

Question 4

main unique of echinoderms

Answer 4

• pentaradial symmetry
• endoskeleton made of calcium carbonate
• ossicles connected by mutable collagenous tissues under neuronal control
• water vascular system

Question 5

pentaradial symmetry

Answer 5

oral and aboral surface. radial bc sessile, sedentary, suspension-feeding.

Question 6

endoskeleton of calcium carbonate

Answer 6

ossicles held together by living tissue

Question 7

ossicles connected by mutable collagenous tissue under neuronal control

Answer 7

soft and floppy to rock hard by changing collagen texture at will. dont waste energy on muscular contractions.

Question 8

special ossicles in sea urchins & starfish

Answer 8

• pedicellariae. look like jaws, pinch thru muscular action

Question 9

water vascular system

- how many coeloms?

Answer 9

5 coeloms. lined with cilia to aid in circulation. fluid no isosmotic with sea water. - add K

Question 10

function of polian vesicle?

Answer 10

help maintain internal pressure

Question 11

tube feet extend how?

Answer 11

hydrostatic pressure form ampulla

Question 12

primary function of water vascular systme?

Answer 12

feeding. locomotion arose later

Question 13

name arms of ehinoderm

Answer 13

opposite madreporite = A

counter clockwise on aboral surface

Question 14

what morphology do echinoderms lack?

Answer 14

brain, cns, ganglia, no excretory organs. lack eyes, no gas-xchange. lack intestine, and anal opening

Question 15

reproduction and development in echinoderms

Answer 15

separate sexes.
broadcast sperm.
may be brooded eggs: lecithorophy, may be braodcast - planktotrophic

larva differ. but have bilateral symmetry.

Question 16

which class is most basal?

Answer 16

crinoidea

Question 17

4 clusters in 2 clades

Answer 17

long-armed: asteroidea, ophiuroidea

armless: echinoidea + ophiuroidea

Question 18

crinoidea

Answer 18

suspension feeders, oral up. pinnules on arms. multiples of 5 arms.
capture suspecded particles, flick to ambulacral grooves. face arms to water flow. oral side is not to flow tho.

Question 19

asteroidea

Answer 19

arms well-developed. not clearly set off from central disk.
oral down. aboral (with madreporite) up.
crawl with tube feet. opportunistic feeders. evert stomach and liquify food.

Question 20

class ophiuroidea

Answer 20

oral + madreporite down. 5 arms clearly demarcated arms

Question 21

class echinoidea

Answer 21

sea urchins, sand dollars.
- armless.
globular = urchin. flat = dollar.
aristotle’s lantern - 5 blade-like teeth. teeth protruded through mouth. grown constantly.

Question 22

class holothuroidea

Answer 22

sea cucumber.
secondarily bilaterally symmetrical. anterior - mouth. posterior - anus.
pentaradial symmetry in tentacles.
- endoskeleton reduces to scattered ossicles. madreporite internal.

Question 23

tubules branch off base of respiratory tree- called?

Answer 23

cuvierian tubules.

Question 24

gut in holothuroidea

Answer 24

retains ancestral torsion loop. deposit feeding - moving tentacles or suspension feeding - more branched tentacles.
-tube feet for locomotion, not feeding.