Invertebrates Crossword Puzzle

QUESTIONS LIST:

• platyhelminthes: flatworms
• trochophore: ciliated larvae of molluscs.
• appendages: arthropods have jointed _ .
• acoelomates: animals that lack a body cavity.
• choanocytes: specialized cells that engulf bacteria by phagocytosis.
• nematocysts: specialized organelles of cnidocytes that function to stun and capture prey.
• diploblastic: cnidarians are _ , meaning they have two tissue layers.
• segmented: annelids are commonly known as _ worms.
• osculum: in sponges, water is drawn into the spongocoel and flows out through the _ .
• visceral: the _ mass contains most internal organs of molluscs.
• mantle: fold of tissue that secretes the shell of molluscs.
• cuticle: exoskeleton made of layers of protein and chitin.
• calcareous: echinoderms have an exoskeleton of hard _ plates.
• metamorphosis: insects undergo incomplete or complete _ .
• decapods: crustaceans such as lobsters, crabs, crayfish, and shrimp.