Bio1152 Chapter 32 An Introduction to Animal Diversity
  1. Animals are multicellular,                eukaryotes that ingest their food.

  2. The ancestor of animals diverged from those of        about 1.2 billion-800 million years ago, and may have resembled modern                    .

  3. The kingdom diversified about 525 million years ago, during the           explosion, when many animal phyla appeared.

  4. Animals can be categorized by how their cells are organized according to a       plan.

    •         symmetry is like a flower pot, the body radiates from the center.

    •            symmetry has a single plane of symmetry.

    • Most animals have          that develop from embryonic layers of the           .

    • Diploblastic animals such as jellyfish have      germ layers:           and           . Triploblastic animals have        germ layers, including a           .

    • The mesoderm may develop into tissue that line a fluid-filled space called a         .

      • A               is a body cavity only partially lined by mesoderm tissues.

      • Organisms without a body cavity are considered              .

  5. The coelomates show two major modes of development.
    • Protostomes develop their        from the blastopore of the gastrula.

    • Deuterostomes develop their       from the blastopore.

  6. Current phylogeny places            as a clade with true          , and divides the Bilateria into three clades:                , Lophotrochozoa, and Ecdysozoa.

Bio1152 Chapter 33 Invertebrates
  1. Invertebrates do not have a           , and account for 95% of known animal species.

  2. Phyla           and          are the multicellular sponges (formerly Porifera) that lack true tissues. Fertilization is external:

  3. Phylum           belongs in the clade with true          called            .

  4. Most Eumetazoa belong to the clade            and exhibit            symmetry and triploblastic embryonic development.
  5. Phylum                  are flatworms with a gastrovascular cavity.

  6. Phylum           are roundworms with a               .

  7. Phylum           are tiny animals, smaller than many protists.

  8. Phylum           are soft-bodied animals.

  9. Phylum           are segmented worms with a true         .

  10. Phylum             have            bodies.

  11. Phylum                are                .