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Invertebrates 1 Sponges 2/20/13 Figure 25.10 Invertebrates 1 Sponges Cnidarians • Diversity of invertebrates Echinoderms – fossil record Chordates • Porifera Brachiopods • Cnidaria Annelids • Lophotrochozoa Molluscs – Annelids Arthropods – Molluscs PROTEROZOIC PALEOZOIC Ediacaran Cambrian 635 605 575 545 515 485 0 Feb 20, 2013 Time (millions of years ago) Figure 33.3a Figure 33.3b Porifera (5,500 species) Placozoa (1 species) Platyhelminthes Ectoprocta Rotifera Brachiopoda (20,000 species) (4,500 species) (1,800 species) (335 species) 0.5 mm A brachiopod A sponge 0.1 mm A marine flatworm Ectoprocts A rotifer (LM) Cnidaria (10,000 species) Acanthocephala Nemertea Cycliophora Annelida (16,500 species) A placozoan (LM) (1,100 species) (900 species) (1 species) Curved Ctenophora (100 species) hooks A jelly 100 µm Acoela (400 species) An acanthocephalan (LM) A cycliophoran (colorized SEM) A marine annelid Mollusca A ribbon worm (93,000 species) 1.5 mm Acoel flatworms (LM) A ctenophore, or comb jelly An octopus Lophotrochozoa Figure 33.3c Figure 33.3d Loricifera (10 species) Priapula (16 species) Onychophora (110 species) Hemichordata Chordata (85 species) (52,000 species) 50 µm A tunicate A loriciferan (LM) A priapulan An onychophoran Echinodermata (7,000 species) Nematoda Tardigrada Arthropoda (25,000 species) (800 species) (1,000,000 species) 100 µm An acorn worm A roundworm (colored SEM) Tardigrades Ecdysozoa A scorpion (an arachnid) Deuterostomia (colorized SEM) A sea urchin 1 2/20/13 Fig. 32-11 “Porifera” Silicea Metazoa Calcarea ANCESTRAL COLONIAL Ctenophora FLAGELLATE Eumetazoa For common invertebrates (eg. Cnidaria jellyfish, spider, sea urchin, etc) you Acoela Deuterostomia Echinodermata should know which phylum it is in and Bilateria Chordata how that fits in the general Platyhelminthes Lophotrochozoa Rotifera phylogenetic classification of animals. • Ectoprocta Why is “porifera” in Brachiopoda quotation marks? Mollusca Annelida Ecdysozoa Nematoda Arthropoda Figure 33.4b For each major group, you Choanocyte should know: • What is the basic body plan? • What are the life stages or Pore developmental stages? Spicules Epidermis • How does it eat? Water flow • How does it move? Amoebocytes Figure 33.4c Figure 33.UN02 Porifera Eumetazoa Food particles Cnidaria in mucus Flagellum Lophotrochozoa Choanocyte Collar Ecdysozoa Deuterostomia Phagocytosis of food particles Amoebocyte 2 2/20/13 Figure 33.5 Figure 33.6 Mouth/anus Tentacle Tentacle Cuticle of prey Gastrovascular cavity Thread Gastrodermis Mesoglea Nematocyst Body “Trigger” stalk Epidermis Tentacle Thread Mouth/anus discharges Polyp Medusa Thread (coiled) Cnidocyte Figure 33.8-3 Figure 33.UN03 Porifera Feeding Cnidaria polyp Bilateria Lophotrochozoa MEIOSIS Ecdysozoa Medusa Egg Sperm Deuterostomia SEXUAL ASEXUAL REPRODUCTION Portion REPRODUCTION of a (BUDDING) colony FERTILIZATION of polyps Zygote Planula (larva) Key Haploid (n) 1 mm Diploid (2n) Figure 33.10 Figure 33.14a Gastrovascular cavity Mouth Eyespots Lophophore Ventral nerve cords Ganglia (a) Ectoprocts, colonial lophophorates 3 2/20/13 Figure 33.17 Figure 33.15 Nephridium Heart Visceral mass Digestive tract Coelom Intestine Gonads Mantle Mantle Stomach cavity Shell Mouth Radula Anus (a) A land snail Gill Mouth Radula Foot Nerve Esophagus (b) A sea slug (nudibranch) cords Figure 33.20 Figure 33.24 Cuticle Coelom Coelom Epidermis Hinge area Mantle Gut Heart Adductor muscle (one or two) Metanephridium Digestive gland Anus Anus Mouth Chaetae Excurrent Intestine siphon Skin Fused nerve cords Clitellum Crop Shell Intestine Giant Australian earthworm Palp Water flow Gizzard Foot Cerebral Mantle Incurrent ganglia Ventral nerve cords Gonad Gill siphon cavity Mouth Circulatory with segmental ganglia system vessels Figure 33.UN06a 4 .
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