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Thin layer of tissue that covers a mollusk's body organs
Organs that exchange carbon dioxide for oxygen in the water
Open Circulatory System
Blood circulation system in which blood moves through vessels and into open spaces around the body organs
Tongue-like organ with rows of teeth used to scrape and tear food
Muscle on the bottom of most mollusks that allows them to move through their environment
Closed Circulatory System
Blood circulation system in which blood moves through the body in closed vessels
Movement through the water by pushing water out through a cavity in the organisms body
Jointed structures of arthropods, such as legs, wings, or antennae
Thick, hard, outer covering that protects and supports arthropods bodies and provides places for muscles to attach
Shedding and replacing of an arthropod's exoskeleton
Openings in the abdomen of insects through which oxygen enters and exits
Process in which many insect species change their body to become adults