1. Biodiversity- Mollusks
Sarah Whitebloom
Matt Jones
Eddie Frere

2. What are the 3 types of mollusks?
Objective: SWBAT describe what a mollusk is, the different types of mollusks, examples, and their functions Warm-Up
What is a mollusk?
What are the 3 types of mollusks?
An invertebrate with a soft, unsegmented body often enclosed in a hard shell containing calcium carbonate
Gastropoda, Bivalvia, Cephalopoda

3. Notes- Mollusks
Mollusk- an invertebrate with a soft, unsegmented body often enclosed in a hard shell containing calcium carbonate
The body is divided into 4parts: foot, visceral mass, mantle, and shell

4. The 4 types
Foot: it has different forms for different circumstances; flat structures for crawling, spade-shaped structures for burrowing, and tentacles for capturing prey
Visceral mass: below the mantle; consists of the internal organs
Mantle: thin layer of tissue that covers most of the body
Shell: made by glands in the mantle that secrete calcium carbonate(not found on all slugs and other mollusk groups)

5. The Body

6. Feeding
Can be herbivores, carnivores, filter feeders, detritivores, or parasites
Snails and slugs get their food using a flexible, tongue-shaped structure called the radula
There are hundreds of tiny teeth attached to the radula
Herbivores use it to scrape the algae off the rocks
Carnivores use it to drill through shells of other animals
Food is carried by water which enters through a siphon: a tube-like structure where water enters and leaves the body

7. Circulation
The oxygen and nutrients are carried through the mollusk body by a circulatory system
It is either open or closed
Open circulatory system: blood is pumped through vessels by a heart
Open circulatory systems work best for slow-moving mollusks because the demand for oxygen is lower
Closed circulatory system: transport blood through an animal’s body much more quickly than an open circulatory system; better for faster- moving mollusks

8. Gastropods
Shell-less or single-shelled mollusks that move by using a muscular foot located on the ventral side
Includes pond snails, land slugs, sea butterflies, sea hares, limpets, and nudibranchs

9. Bivalves
Two shells that are held together by one or two powerful muscles
Includes clams, oysters, mussels, and scallops

10. Cephalopods
Soft-bodied mollusks in which the head is attached to a single foot
The foot is divided into tentacles or arms
Most active mollusks
Octopi, squids, cuttlefishes, and nautiluses

11. Activity

12. Activity round 1 Mollusk Open-circulatory system Cephalopod
Closed-circulatory system
Gastropod
Bivalve
Foot
Radula
Visceral mass
Mantle

13. Activity round 2 Good for slow moving mollusks
Food is carried by water and enters through the…
Octopi
Oxygen and nutrients carried through the body by a…
Move with a muscular foot
Tiny teeth attached to the…
____ drill through shells of other animals
Blood pumped through vessels by a heart
____ scrape algae off rocks
Two shells held together by one muscle

14. Activity round 3 Shell Sea butterflies Soft-bodied mollusks Siphon
Most active mollusks
Below the mantle
Clams
Thin layer of tissue
Shell-less/single-shelled
Not found on slugs

15. Wrap-Up What is a mollusk? What are the 3 groups?
What are the 4 parts in the body plan?