Transcript Animals I
The Animal Kingdom Part 1 General Characteristics: Exhibit multicellular construction Composed of eukaryotic cells Nutrition is by ingestion Animals differ from plants • Contain centrioles & asters • Lack chlorophyll, plastids, cell walls • Exhibit both embryonic and larval stages • Exclusively heterotrophic General Characteristics: Complex organisms - up to 10 systems 1) Skeletal 2) Muscular* 3) Endocrine 4) Nervous* 5) Circulatory 6) Lymphatic 7) Integumentary 8) Reproductive 9) Excretory 10)Respiratory 11) Digestive * Unique to animals General Characteristics: Adult form may be viewed as a complex tube within a tube Reflected by the presence of 3 primary germ layers: – Ectoderm – integument & nervous – Mesoderm – muscles and most other organs – Endoderm – lines digestive tube General Characteristics: Reflected by the presence of 3 primary germ layers: – Ectoderm – integument & nervous – Mesoderm – all other systems – Endoderm – digestive Triploblastic – possess all 3 germ layers Diploblastic – possess only 2 germ layers General Characteristics: Exhibit the Diplontic Life Cycle (sexual reproduction) • • • Adult 2N Gamete 1N Zygote 2N Adult 2N egg 1N mitosis Zygote 2N meiosis sperm 1N Domain Eukarya Animal Classification Broad Classification 1) 2) 3) 4) Level of Organization Type of Body Symmetry Type of Body Cavity Embryonic Development Level of Organization IF the cell develops from a single cell to the tissue level only, it belongs to Subkingdom Parazoa (beside the animals) Phylum Porifera - sponges (to bear pores) Level of Organization All others develop to an organ or organ system level: Subkingdom Eumetazoa (true later animal) Type of Body Symmetry 1. Only sponges lack symmetry (asymmetrical) 2. Organisms whose body parts are organized around a central axis and radiate from the central core like the spokes of a wheel exhibit radial symmetry. (Think of an orange.) 3. Organisms whose body parts are arranged along a longitudinal axis where right and left half are mirror images of each other exhibit bilaterial symmetry. (Think of a butterfly.) Type of Body Symmetry Radially symmetrical organisms belong to Grade Radiata Type of Body Symmetry Bilaterially symmetrical organisms belong to Grade Bilaterata Type of Body Symmetry Grade Radiata larva, ancestors, AND adults are radially symmetrical Phylum Cnidaria - jellyfish Another typical Cnidarian: Hydra Cnidarian forms Type of Body Symmetry All others belong to the Grade Bilaterata larva, ancestors, OR adults are bilaterally symmetrical Type of Body Cavity (coelom) Subgrade Acoelomata Phylum Platyhelminthes -the flatworms NO body cavity Solid layer of mesoderm ectoderm solid mesoderm endoderm gut Type of Body Cavity (coelom) Subgrade Pseudocoelomata Phylum Nematoda -the roundworms False cavity (false coelom) Pseudocoel only partially lined with mesoderm Endoderm Ectoderm w/ mesoderm lining Pseudocoel Gut Type of Body Cavity (coelom) Subgrade Coelomata Phyla Annelida Chordata True body cavity Coelom completely lined with mesoderm ectoderm Coelom (completely lined with mesoderm) endoderm gut Body Plans Choanoflagellates Protist Link to Animals? Embryonic Development/ formation of the archenteron Type of Embryonic Development If the first opening into the blastocoel is the mouth, the organism is a Protostome. Type of Embryonic Development If the second opening into the blastocoel formed is the mouth, the organism is a Deutrostome. A family tree