ANIMAL KINGDOM

ANIMALS ANIMAL CHARACTERISTICS Eukaryotics Multicellular Lacking cell wall Heterotrophs (ingest and digest) Mobile or have mobility in at least one life stage Sexual reproduction, produce an embryo

ANIMALS CHARACTERISTICS USED TO CLASSIFY ANIMALS Invertebrate or Vertebrate Levels of organization Number of body layers Symmetry and body plans Body cavity Segmentation Movement Reproduction

ANIMALS INVERTEBRATE OR VERTEBRATE INVERTEBRATE: no backbone, 95% VERTEBRATE: internal skeleton and backbone, 5%

ANIMALS LEVELS OF ORGANIZATION Differences in structure, tissues, organs and organ systems All have cells All have tissues (except sponges)

ANIMALS NUMBER OF BODY LAYERS All animals have three cell layers (except sponges and phylum cnidaria-corals, hydras, jelly fish and sea anemones) Layer 1 endoderm = inner layer: lungs, liver, pancreas, bladder, stomach lining Layer 2 mesoderm = middle layer: muscles, blood, kidneys, reproductive organs Layer 3 ectoderm = outer layer: skin, nerve tissue, sense organs All layers develop during early embryo growth Layers help sort cells into arrangements for specialized tissues and organs

ANIMALS NUMBER OF BODY LAYERS

ANIMALS SYMMETRY AND BODY PLANS Different arrangements of cells, tissues and organs leads to different body plans Asymmetrical = irregular body shape Radial Symmetry = divided along any plane parallel to body axis Example: corals, jellyfish Bilateral Symmetry = divided into two mirror halves only along one plane through the central axis Example: worms, insects, vertebrates

ANIMALS SYMMETRY AND BODY PLANS

ANIMALS BODY CAVITY Coelom: fluid filled cavity that provides space for the development and suspension of organs and organ systems Gives muscles a structures to brace against, allowing quick movement and recovery Allows increased complexity Coelomates: worms, molluscs, insects, vertebrates Acoelomates: corals, jellyfish, flatworms

ANIMALS BODY CAVITY

ANIMALS SEGMENTATION Segmentation: the division of the body into repetitive sections Advantages: If a single segment is damaged, other segments can continue to function properly - Increased mobility

ANIMALS SEGMENTATION

ANIMALS MOVEMENT Nerve and muscle tissue allow complex and fast movement Sessile: stationary, live attached to one place; juvenile development allows for movement Ex: sponges, sea anemones

ANIMALS MOVEMENT

ANIMALS REPRODUCTION Sexual: gametic Zygote = diploid organism = gametes = fertilization = zygote… 2 types of fertilization: External: gametes combine outside body, mostly aquatic Ex: fish, amphibians Internal: gametes combine inside body Ex: humans Asexual: typically asexual though sexual reproduction can occur during harsh conditions Ex: aphids

ANIMALS REPRODUCTION