Echinodermata
echinoderms:
Overview L77
slides:
starfish pedicellaria
L79 Fig 11.8; T496 Fig 20.11; R75
starfish bipinnaria
larvae L14 Fig 2.2(l); T506 Figs 20.22
& 20.23; R110
starfish arm c.s.
external anatomy of:
sea
star
L76 Fig 11.8; T494 Fig 20.6; R75
sea
lily (in plastic block)
sea urchin c.s. L81 Figs 11.14 and 11.15; T501 Fig 14.12 – spines, mouth, pedicellaria,
madreporite, Aristotle's lantern
Questions for your lab notebook
What are the two functions of the unique water vascular system of echinoderms?
What role does the madreporite play in the water vascular system of echinoderms?
Why are ossicles classified as an endoskeleton?
Which of the following structures in echinoderms does not play a role in gas exchange?
a) dermal branchia
b) respiratory tree
c) Aristotle's lantern
d) coelomic fluid
What factors have led zoologists to determine a close evolutionary relationship between modern echinoderms and chordates (our own phylum)?
Explain how radial symmetry and the lack of cephalization can have adaptive value for sessile animals and be favored by natural selection.