What are the two types of digestive systems invertebrates may have?
gastric and monogastric
complete and simple
complete and fluid
complete and incomplete
Invertebrates have one of two types of digestive system. They are called incomplete and complete digestive systems. Both are shown in Figure below . An incomplete digestive system consists of a digestive cavity with one opening. The single opening serves as both mouth and anus. A complete digestive system consists of a digestive tract with two openings. One opening is the mouth. The other is the anus.