1. Introduction to Animal Kingdom http://artfiles.art.com/images/-/James-Himsworth/Animals-II-Print-C10069671.jpeg

2. Basic Characteristics Multicellular eukaryotes Heterotrophic Movement Sexual Reproduction

3. Multicellular Organization is Important Most animals contain many cells –Example: humans have ~50 trillion cells Most have specialized cells that form tissues and organs; think of it as a division of labor –Has allowed animals to evolve and adpat to certain environments

4. Heterotrophy… All depend on autotrophs for food directly or indirectly They have to ingest their food, meaning they must digest it Digestion is internal, allowing animal to get proteins, carbohydrates and lipids

5. Movement Most animals are able to move, which is a result of specialized nervous and muscular tissue Animals that cannot move are sessile, very few animals are sessile

6. Sexual Reproduction & Development Most reproduce sexually Sexual reproduction increases genetic variation Fertilized egg cell is called a zygote, all animals develop from Fertilization can be internal or external (sperm cell must penetrate egg cell) During development, zygote undergoes many mitotic divisions… these cells must then undergo differentiation Differentiation is when cells become specialized

7. Development Protostome –Opening in gastrula becomes mouth of animal –Examples: mollusks, annelids, arthropods Deutrostome –Mouth develops from second opening –Examples: echinoderms, chordates

8. Body Structure Symmetry Germ Layers Body cavities

9. Symmetry Symmetry describes the arrangement of body structures that enable animals to move in different ways Animals have 3 patterns of symmetry: 1.Asymmetry – no symmetry 2.Radial Symmetry – similar parts branch in all directions from a central point 3.Bilateral Symmetry- similar halves on either side of a central plane.

11. Identify the Type of Symmetry:

12. Germ Layers Tissues found in all animals, except sponges –Ectoderm (outside layer, forms skin) –Endoderm (forms digestive tract) –Mesoderm (forms muscle tissue and most other organs)

13. Body Cavities A fluid filled space separating the digestive tract from the outer body wall; this space is known as coelom Functions: –Suspends organs to prevent internal injury –Enables organs to grow and move independent of outer body wall

14. Types of body cavities: Acoelomate (no body cavity) –Solid body, no cavity separating digestive tract from outer body wall –least complex body plan –Examples: flatworms Pseudocoelomate –cavity not completed lined by mesoderm tissue –Examples: roundworms and rotifers Coelomate –True body cavity; completely lined by tissue of mesoderm –most complex body plan –Examples: mollusks, annelids, arthropods, echinoderms, and chordates

16. Origin of Animals 1 st evolved from the sea Zoologists today recognize ~35 phyla based evolutionary relationships