The document discusses the phylum Mollusca, describing some of its key characteristics and classes. It outlines the body plans and systems of mollusks, including their circulatory, respiratory, and nervous systems. Specific structures like the radula, operculum, and shells are examined. Reproductive processes vary between external fertilization and hermaphroditism. Examples are provided of mollusk classes like bivalves, gastropods, and cephalopods to illustrate their diversity.

1. ANIMALIA
Standar Kompetensi
Siswa mampu m emahami prinsip-prinsip pengelompokkan
makhluk hidup.
Kompetensi Dasar
2.6 Mendeskripsikan ciri-ciri filum dalam dunia Hewan
dan peranannya bagi kehidupan
Indikator
 Mengenal ciri-ciri umum animalia.
 Mengidentifikasi karakteristik berbagai filum anggota kingdom
animalia.
 Menyajikan data (gambar, foto, deskripsi) berbagai ivertebrata
yang hidup di lingkungan sekitarnya berdasarkan pengamatan.
1

2. Phylum MOLLUSCA
 Class Polyplacophora - Chiton

3. Phylum Mollusca
 Class Scaphopoda – Tusk Shells

4. Phylum Mollusca
 Class - Gastropoda

5. Phylum Mollusca
 Class Gastropoda - Nudibranch

6. Phylum Mollusca
 Class – Gastropoda - Nudibranchs

7. Phylum Mollusca
 Class – Sea Hare

8. Class Gastropoda
 whelks

9. Class - Gastropoda
 Conch

10. Class Gastropoda
 Limpets and Periwinkles

11. Class - Gastropoda
 Abalone

12. Class - Gastropoda
 Land Snail

13. Class Bivalvia
 Clams, Mussels,Scallops

14. Class - Cephalopoda
 Squid
 Octopus

15. Class Cephalopoda
 Octopus

16. Class Cephalopoda
 Nautilus

17. Characteristics of Molluscans
 Size – Millimeter to 60 Feet (18M)
 Major Food source
 Lifestyle
Simple - Limpets
Complex – Squid and Octopi

18. Molluscan Body Plan
 Visceral Mass
 Foot
 Adductor Muscles
 Siphons
 Gills

19. Circulatory System
 Open Circulatory System
Means that not all the blood is
contained in vessels but rather
vessels AND open chambers called
sinuses
Sinuses take place of the Capillaries
3 chambered heart

20. Body Systems
 Respiration – this is accomplished thru
the circulation of oxygen-rich water by
the MANTLE
 Excretion – this is accomplished by
Kidneys that double as a passageway
for eggs or sperm
 Nervous System – varies with species.
Limpets and Bivalves are simple,
Cephalopods are well developed.

21. Comparison of Body Plans

22. Specialized Structures
 Radula – Horny-toothed structure found
within the pharynx
Used for “Rasping” or “Scraping” plant or
animal tissue
Bivalves are filter feeders and have lost
this structure
Cephalopods, in addition, have a “Beak”
which work together to kill prey

23. Specialized Structures
 Operculum – A protective plate that
covered the opening to the shell of
some gastropods
 Siphon – A tube that allows for water to
enter/leave the body of a Mollusc.
Bivalves and Cephalopods
 Siphuncle – a cord of tissue that
connects all the chambers of the
Nautilus and used for boyancy

24. Specialized Sturctures
 Nacre – secretion around sand particles
by oysters resulting in a pearl.
 Hectocotylus – a special structure on
one of the arms of an Octopus (male)
that allows it to deposit sperm packets
into the females mantle cavity

25. Hectocotylus

26. Specialized Structures
 Shells – Not all mollusc’s produce them
Make of calcium carbonate which is
obtained from water or soil.
They can grow through the lifetime of
the animal

27. Reproduction
 Varies tremendously from external
fertilization to internal, dioecious and
hermaphrodidic
Changing Sex – some such as oysters
change back and forth from male to
female releasing sperm and eggs
accordingly.
Spermatophores – packets of sperm