Mollusks and Annelids Crossword

Across
1.	Second-largest phylum of invertebrate animals that contain snails, octopuses, squid, and clams
5.	The largest Mollusca phylum that contains slugs and snails
8.	A shelled gastropod molluscs
9.	The only cephalopod with a external shell
11.	Segmented worms like earthworms, polychaetes, and leeches
12.	A pair of muscular bristle appendages
13.	Respiratory system of aquatic animals that extract oxygen from flowing water
15.	A tube that allows for water to exit the mantle cavity of a bivalve
18.	A soft and non-muscular region of a mollusc that contains body organs
20.	Gastropods molluscs that do not have a shell
21.	A body tissue that makes a shell

Down
2.	Segmented parasitic or predatory worms in the phylum Annelida
3.	Cells that produce color to create camouflage
4.	A long slender appendage of an animal around the mouth or head of a animal
6.	The segment of a aorta that helps distribute blood to the head and upper extremities
7.	Predatory mullusk such as squid and octopus
10.	A Cephalopod mollusk with ten arms and tail fins
14.	Bristles that allow for movement
16.	A structure of tiny teeth used for scraping food particles off a surface to go into the mouth
17.	A tube that allows entrance for water containing food and oxygen
19.	Mollusks that have two shells held together by hinges and strong muscles