Ectoderm, mesoderm and endoderm give rise to all animal tissues; simple animals have only two.
Diploblasts (cnidarians) have ectoderm and endoderm; triploblasts add mesoderm, enabling complex organs like muscles and circulatory systems.
Germ layers determine tissue types. Triploblasts have more organ complexity. Fate is shown in fate maps.
Remember: ectoderm is outer, endoderm inner.
Ectoderm, mesoderm and endoderm give rise to all animal tissues; simple animals have only two.
Germ Layers is one of the 53 topics in Zoology & Animal Diversity. It is rated Intermediate, so it suits learners who already know the core vocabulary. Related topics in this area include Body Cavities, Vertebrates and Invertebrates, Animal Kingdom.
In vertebrates, the notochord and heart develop from mesoderm.
Work through the Beginner topics in Zoology & Animal Diversity first, such as Animal Kingdom, Vertebrates and Invertebrates, Sponges, then return to Germ Layers. Intermediate topics assume the Beginner vocabulary.
The closest topics to Germ Layers are Body Cavities, Vertebrates and Invertebrates, Animal Kingdom, Animal Symmetry. Comparing them side by side is a good way to see how the ideas connect.
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Germ Layers. To practise the whole of Zoology & Animal Diversity, use the Zoology & Animal Diversity quiz.
Germ Layers: Ectoderm, mesoderm and endoderm give rise to all animal tissues; simple animals have only two. Body Cavities: Acoelomate, pseudocoelomate and coelomate animals differ in how the fluid-filled cavity around organs is formed. Read both side by side and note what each one explains.
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Body Cavities and explain the difference aloud. Finally, take the Zoology & Animal Diversity quiz and come back to this page for any question you miss.
Acoelomate, pseudocoelomate and coelomate animals differ in how the fluid-filled cavity around organs is formed.
🦁 Zoology & Animal DiversityVertebrates have a backbone; invertebrates, which are over 95 percent of animals, do not.
🦁 Zoology & Animal DiversityMulticellular heterotrophic eukaryotes without cell walls that typically move and ingest food.
🦁 Zoology & Animal DiversityAnimals show radial, bilateral or no symmetry, which relates to their lifestyle and movement.
🦁 Zoology & Animal Diversity