(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.
The earthworm takes in a mixture of soil and organic matter through its mouth, which is the beginning of the digestive tract. The mixture enters the pharynx, which is located in segments 1 6. The esophagus, in segments 6 13, acts as a passageway between the pharynx and the crop. The crop stores food temporarily. The mixture that the earthworm ingests is ground up in the gizzard. In the intestine, which extends over two-thirds of the body length, digestion and absorption take place. Soil particles and undigested organic matter pass out of the worm through the rectum and anus.