(of fish) migrating from salt water to spawn in fresh water, as salmon of the genera Salmo and Oncorhynchus (distinguished from catadromous). Origin of anadromous.
A: A snail scrapes its food, rather than chews it like we humans do. A flexible structure called the radula in the snailâs mouth is lined with neatly organized rows and columns of tiny tooth-like projections. The snail moves its radula over the food, scrapes off bits of it, and swallows.
An earthworm 's digestive system consists of a mouth, pharynx, esophagus, crop, gizzard, and intestine. The mouth is surrounded by strong lips, which act like a hand to grab pieces of dead grass, leaves, and weeds, with bits of soil to help chew. The lips break the food down into smaller pieces.