1. Chapter 2 Section 1 Animals
Mollusks
Chapter 2
Section 1
Animals

2. What are Mollusks? Invertebrates Soft unsegmented bodies
Often protected with hard shells
Mantle
Thin layer of tissue protecting organs
Produces the shell

3. What are Mollusks? Move with a muscular foot Live everywhere
Adapted for variety of uses
Live everywhere
Water, mountains, trees, oceans, land
Bilateral symmetry

4. What are Mollusks? Internal organs all located in one area Kidneys
Filter wastes
Gills
Remove oxygen from water
Radula
Flexible ribbon of teeth

5. Evidence of Early Mollusks
Lived in Earth’s oceans
540 million years ago
Evidence in limestone rocks
Layers of broken shells fell to ocean floor
Chemical reaction caused cementation
Some shells didn’t break and were preserved in the rock

6. Snails and their Relatives
Gastropod
Stomach foot
Shells
Single
Coiled
None

7. Snails and their Relatives
Habitat
Anywhere
Herbivore
Carnivore
Scavenger
Defense
Curl up in shell and close trapdoor

8. Two Shelled Mollusks Bivalves Two shells Held together by hinges
do not have radula
Filter feeders
Use gills to capture food as they breath

9. Two Shelled Mollusks Found in watery environments
Stay put or move slowly
Oysters and mussels attach to a surface
Clams dig into the sand
Scallops clap their shells together to “swim”

10. Two Shelled Mollusks Grit lodged in a bivalve cause an irritation
Mantle coats the grit
Becomes covered in a pearly coat
pearls

11. Mollusks with Tentacles
Cephalopod
Octopus
Cuttlefish
Nautiluses
squid

12. Mollusks with Tentacles
Shell
Nautilus external shell
Squid and cuttlefish internal shell
Octopus no shell
Obtain food
Capture with tentacles
Keen sense of touch and taste

13. Mollusks with Tentacles
Large eyes
Excellent vision
Large brain and complex nervous system
Live in the oceans only