what is an echinoderm's tubular gut?

Question

we have a project due Monday.. need answers quick!!!

Answer 1

This means the main tube that the food goes through during digestion. It's referred to as tubular because echinoderms have a complete digestive system with two body openings, the mouth and anus. Food goes in one direction through the system, in the mouth, through the system, and out the anus.

An incomplete system has one body opening, the mouth, and food goes in through the mouth to a digestive cavity. Undigested food goes back out through the mouth. This is not a one-way system and is less efficient.