Meet the mollusks & arthropods

1. Meet the Mollusks &
Arthropoda
Kingdom Animalia!

2. Phylum Mollusca
•2
nd
largest phylum; more advanced than
the last 3
•3 Classes we’ll cover:
A) Gastropods – “stomachs with feet”
B) Bivalves – “2 shells”
C) Cephalopods – “heads with feet”

3. A) Class Gastropoda
•The Snails &
Nudibranchs!
–Some (snails) make
their own shell
–Snails move using a
foot
–Snails have an
operculum – “Trap
Door” slams shut to
protect snail inside
–Nudibranchs = shell-
less snails
Nudibranch:
http://www.youtube.com/watch?v=FysyIFFNXl8&NR=1&feature=fvwp

Snail:
http://www.youtube.com/watch?v=BMOSvz5mThM

4. B) Class Cephalopoda
•The Squid and
Octopus!
–Most evolved
mollusks
–Have beaks and
tentacles
–Ink
–Squids are largest
invertebrate, but
octopus are the
most intelligent

5. Octopus smart & flexible!
•http://animal.discovery.com/videos/fooled-by-nature-intelligent-octopuses.html

6. C) Class Bivalvia
•The Clams, mussels, scallops – oh my!
–2 shells
–Most use foot to move, but scallops swim!
http://video.google.com/videoplay?docid=-5451171616065371182&q=swimming+scallop&total=30&start=0&num=10&so=0&type=search&plindex=6

7. Phylum Arthropoda
•Still Kingdom Animalia!
•Two Subphyla We’ll Cover:
A) Subphylum Chelicerata – Sea Spiders &
Horseshoe Crabs
B) Subphylum Crustacea – Lobsters, Crabs,
Shrimp, for example

8. The only “attached”
crustacean
Can you name them?

9. •Subphylum Chelicerata
a. Sea Spiders and b. Horseshoe Crabs
Like all Arthropods, they have no bones and
grow by molting!

10. a. Class Pycnogonida
(sea spiders-yipes!)

11. b. Class Merostomata
Horseshoe Crabs are
True Blue Blooded
Creatures
We have ____________________ to make our blood
red
Many crustaceans have hemocyanin, making their
blood blue!
http://www.youtube.com/watch?v=e8KlAmtIu1E

12. Male
Horseshoe
Crabs
Have
Modified
Front Legs
That Look
Like
Boxing
Gloves or
Baseball
Mitts to
Help Hold
onto the
Female
During
Mating

13. http://horseshoe-crabs.com/Horseshoe_crab_anatomy_video.html

14. 2. Subphylum – Crustacea – Lobsters,
Crabs, and Shrimp – oh my!

15. More Crustaceans:
the sea insects
Scuds, Beach Hoppers, Beach Fleas, and Skeleton Shrimp:
The Amphipods

16. Still that familiar
meroplanktonic
larvae we know and
love! Special Name:
Zoea

17. Still No Skeleton – Molting Instead

18. The Smallest, Most Abundant
Crustacean in the World’s
Oceans:
The Little Copepod
??What’s the largest
Crustacean??
Are You “CooCoo” for Copepods?
Krill Kill Memory Jogger – why
is this Crustacean Arthropod
sad ?
“Help me!. . . . .I have no ice left to live
in!”. . . . “My world is melting!. . . What am
I supposed to eat?”. . . Where are all
these jellyfish coming from?. . . 

19. What’s Going On Here????
http://www.youtube.com/watch?v=yMxY4c5SeIs
http://news.nationalgeographic.com/news/2006/09/060921-krill-video.html

20. http://library.thinkquest.org/J001418/what.html
Which Numbers Belong To Which
Phyla?
(Try the rest for a good review before
the unit test!)

21. References (on our class website)
•http://www.dnr.state.md.us/baygame/bbc_molting.asp
•http://www.k12.de.us/warner/structure.html