[坎贝尔生物学 第735页] Campbell Biology 12th Edition
33 An Introduction to Invertebrates KEY CONCEPTS 33.1 Sponges are basal animals that lack tissues p. 690 33.2 Cnidarians are an ancient phylum of eumetazoans p.
33 An Introduction to Invertebrates KEY CONCEPTS 33.1 Sponges are basal animals that lack tissues p. 690 33.2 Cnidarians are an ancient phylum of eumetazoans p.