1 / 11

Mollusk Life Cycle

Mollusk Life Cycle. Most mollusks are dioecious (separate sexes) Some are hermaphroditic The life cycle of many mollusks includes a free swimming, ciliated larval stage called a TROCHOPHORE. Major Mollusk Classes. Four major classes of mollusks: Class Polyplacophora – the chitons

purity
Télécharger la présentation

Mollusk Life Cycle

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. Mollusk Life Cycle • Most mollusks are dioecious (separate sexes) • Some are hermaphroditic • The life cycle of many mollusks includes a free swimming, ciliated larval stage called a TROCHOPHORE

  2. Major Mollusk Classes • Four major classes of mollusks: • Class Polyplacophora – the chitons • Class Gastropoda – snails & slugs • Class Bivalvia – clams, mussels, oysters • Class Cephalopoda – octopus & squid

  3. Class Polyplacophora • Includes the chitons • Eight overlapping shell plates • Can roll up • All marine • Use radula to scrape algae off rocks.

  4. Class Gastropoda • largest of the mollusk classes • 70,000+ named species • Include snails, slugs, nudibranchs (sea slugs), sea butterfly • Marine, freshwater, terrestrial • Creep along using foot

  5. Class Gastropoda • The shell of a gastropod is always one piece, called a valve. • Gastropods are considered univalves

  6. Class Gastropoda • Many snails can withdraw into the shell and close it off with a lid called an operculum.

  7. Class Gastropoda • Nudibranchs are sea slugs • Do not have shell • Have colorful branches of gut or gills exposed • Prey on sponges, cnidarians, & other invertebrates • May produce noxious chemicals

  8. Class Gastropoda- Nudibranchs

  9. Class Gastropoda- Nudibranchs

  10. Gastropod Feeding Habits • Most gastropods are herbivores and feed by scraping algae off of rocks using the radula. • Some (like nudibranchs) are carnivores

More Related