1 / 14

Phylum Mollusca

Phylum Mollusca. Class Scaphopoda Class Cephalopoda. Class Scaphopoda. Defining characteristics Tusk shaped conical shells, open at both ends Development of anterior thread-like adhesive feeding tentacles Elongated tapering tubular shells that burrow in sandy bottoms. Class Scaphopoda.

xaviera-camacho
Download Presentation

Phylum Mollusca

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Phylum Mollusca Class Scaphopoda Class Cephalopoda Class Scaphopoda & Cephalopoda

  2. Class Scaphopoda • Defining characteristics • Tusk shaped conical shells, open at both ends • Development of anterior thread-like adhesive feeding tentacles • Elongated tapering tubular shells that burrow in sandy bottoms Class Scaphopoda & Cephalopoda

  3. Class Scaphopoda • Commonly called tooth shells or tusk shells • Have lost ctenida along with ability to filter feed • Never spirally wound but grows linearly Class Scaphopoda & Cephalopoda

  4. Class Cephalopoda • Defining characteristics • Closed circulatory system • Foot modified to form flexible arms and siphons • Ganglia fused to form a large brain encased in a cartilaginous cranium Class Scaphopoda & Cephalopoda

  5. Cephalopod Characteristics • The most highly organized of all the molluscs, the foot is closely associated with the head • Can be as large as 1,000kg. and 18m. • Architeuthis spp. Class Scaphopoda & Cephalopoda

  6. Defensive Mechanisms • Since they are susceptible to predation they have evolved chromatophores • An ink sac that is associated with the digestive system and discharged out the anus Class Scaphopoda & Cephalopoda

  7. Sensory & Nervous System • Eyes • All but the nautilus have image forming eyes that are like mammals • Convergent evolution Class Scaphopoda & Cephalopoda

  8. Reproduction • Sexes are separate • Males have one modified arm (hectocotylus) for sperm transfer • Sperm are enclosed in packets called spermatophores Class Scaphopoda & Cephalopoda

  9. Squid • 10 sucker bearing arms surround the mouth • 2 longer tentacular arms can shot forward and capture prey • Form large schools and feed on crustaceans, and fishes • The shell is reduced and lies under the mantle • Large folded gills and a circulatory system distribute oxygen quickly Class Scaphopoda & Cephalopoda

  10. Squid Internal Anatomy Class Scaphopoda & Cephalopoda

  11. Squid Locomotion • The foot forms the funnel • The upper end of the mantle is extended into a pair of triangular fins • Can move very quickly • 5-10 m/s Class Scaphopoda & Cephalopoda

  12. Octopus • Have 8 arms all equal in length • Rows of suckers from base to tip • Compact body with a greatly reduced shell • The body is extremely flexible and assumes a streamlined shape when swimming with squid-like jets through the funnel Class Scaphopoda & Cephalopoda

  13. Learning and Memory • Benthic feeders on bivalves, crabs and fishes • Amazing ability to learn quickly and remember for several weeks Class Scaphopoda & Cephalopoda

  14. Could an Octopus be your next Professor? Class Scaphopoda & Cephalopoda

More Related