KEY CONCEPT More than 95 percent of all animal species are invertebrates .

1. KEY CONCEPTMore than 95 percent of all animal species are invertebrates.

2. Scientists have identified 1.3 million living species of animals Overview: Welcome to Your Kingdom

3. Eukaryotic Multicellular Heterotrophic…via ingestion Cells do not have cell walls, but instead are held together by collagen How do you define “animals”?

4. Invertebrates vs. Vertebrates. • Vertebrates have an internal segmented backbone. • Invertebrates do not have a backbone. • Invertebrates encompass most animal groups.

5. head tail fruit fly genes human HOX-B genes tail head Each animal phylum has a unique body plan. • Differences in body plans result from differences in the expression of Hox genes. • Hox genes tell embryonic cells which body part to become. • Mutations in Hox genes led to the vast diversity of animal species.

6. Three criteria are used to categorize animals. body plan symmetry mouth gastrovascular cavity mesoglea brain muscle hearts blood vessels oral arms tentacles mouth digestive track segment nerve cord Animals are grouped using a variety of criteria. • tissue layers • developmental patterns

7. bilateral symmetry: body dividesequally along one plane • There are two types of body plan symmetry. Animals with bilateral symmetry can be divided equally along only one plane, which splits an animal into mirror-image sides.

8. There are two types of body plan symmetry: • radial symmetry: body arranged in circle around a central axis. Animals with radial symmetry have body parts arranged in a circle around a central axis.

9. Animal body plans also vary according to the organization of the animal’s tissues. Sponges and a few other groups lack true tissues Tissues

10. Bilateral animals have three distinct layers of tissue; radial animals have only two. • both animal types have ectoderm (covers surface) and endoderm (inner layer, lines digestive tract) • bilateral animals have mesoderm (middle)

11. Animals are divided into two major groups, the protostomes and the deuterostomes. • Protostomes form mouth-first, and anus second. • Deuterostomesfirst form the anus and then the mouth.

12. Protostomes and deuterostomes are the two majorradiations on the animal phylogenetic tree. Annelida Porifera Cnidaria Platyhelminthes Echinodermata Mollusca Arthropoda Nematoda Chordata Segmented worms sea stars, sea urchins sponges clams, snails, octopuses flatworms lancelets, vertebrates crustaceans, insects, spiders roundworms jellyfish, coral, anemones RADIAL DUETEROSTOMES PROTOSTOMES NO TISSUES A comparison of structure and genetics reveals the evolutionary history of animals.

13. The current organization of the animal kingdom shows some unexpectedrelationships. • Technological advancementshelp to clarify evolutionaryrelationships.

14. Animal Diversity Lab • You will be given a lab sheet with organisms (or samples from organisms) that are in Kingdom Animalia. • You will record the Kingdom, Phylum, and Common name for the organism in your lab journals. • You will draw, color, and label organisms as seen under the microscope.