Across
- 5. A respiratory organ used to extract dissolved oxygen from water and, in some mollusks, to filter food particles.
- 6. A respiratory structure that extracts oxygen from water; in bivalves, it also helps filter food.
- 7. The concentration of sense organs and nerve cells at the anterior (front) end of the body, essentially forming a head.
- 8. A specialized layer of tissue that covers the internal organs and, in many species, secretes the calcium carbonate used to create a shell.
- 9. A tube-like structure through which water enters or leaves the body, used for breathing, feeding, or "jet propulsion" movement.
- 10. A group of highly intelligent, "head-footed" marine mollusks with tentacles, such as squids, octopuses, and nautiluses.
Down
- 1. A flexible, tongue-like organ covered in tiny teeth that mollusks use to scrape, tear, or drill for food.
- 2. A type of body plan where the right and left sides are mirror images of each other.
- 3. A class of mollusks (like snails and slugs) typically characterized by a single shell or no shell and a large, muscular "stomach-foot."
- 4. A group of aquatic mollusks, such as clams and oysters, that have a compressed body enclosed within a hinged, two-part shell.
- 9. The hard, protective outer layer of many mollusks, often made of calcium carbonate.