The distinction between sponges and other animal phyla is based mainly on the absence versus the presence of

Question

Quizplus · Accepted Answer

Sponges lack true tissues, whereas all other animal phyla have them.

Note: Option A is incorrect because not all animal phyla have a body cavity (e.g. flatworms). Option B is incorrect because some animals, such as jellyfish, have a incomplete digestive tract. Option C is incorrect because not all animals have a circulatory system (e.g. flatworms). Option E is incorrect because sponges lack mesoderm, but some animals such as cnidarians also lack mesoderm.

The Distinction Between Sponges and Other Animal Phyla Is Based