An advantage of an alimentary canal over a gastrovascular cavity is that the alimentary canal

An alimentary canal is a digestive tract that is complete and has two openings which are the mouth and the anus. On the other hand a gastrovascular is a digestive tract that has only one opening. The advantage of the alimentary canal is the fact that intake of food can still  go on even during digestion. This will enable a more complete digestion. 

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