Bio 101 - Lecture 7

Bio 101 - Lecture 7 - Announcements Newspaper articles to...

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Unformatted text preview: Announcements Newspaper articles to be read for quiz: "Europe's Appetite for Seafood Propels Illegal Trade" NYT 15 Jan 08 "A Finnish Turf Battle Pits Wolf Against Reindeer Herder" NYT 21 Jan 08 "CDC "CDC recommends new drug for 'superbug' gonorrhea" gonorrhea" (blog article) Evolution of the Animal Body Form Quiz covers lectures on Jan. 22 and 24 and newspaper articles above Animalia Question 1: What's an Animal? What s Characteristics Multicellular Heterotrophs Asexual and Sexual Reproduction Movement Classification: Symmetry Coelom Notochord; dorsal, hollow nerve cord Question 2: How has the animal body plan changed over evolutionary time? Way # 1 Symmetry - Balance of form No symmetry Radial Symmetry Circular, disk or spherical form Top and bottom but no front, back, or sides. e.g., ball, pizza Bilateral Symmetry Body divided along a single plane with right, left, top, bottom e.g., YOU 1 Radial Bilateral Way #2: The Body Cavity or Coelom in Animals (not to be confused with the dental cavity in teeth) Fig. 23-2, p.361 Way #3 Backbone? Invertebrates no Vertebrates - yes Fig. 16.6 Animal Diversity Most animal groups appeared between 500 and 600 million years BP There are more animal species than everything else put together (1,500,000 described so f ) d ib d far) Over 95% are invertebrates Of those, most are insects 2 Invertebrates No Symmetry, No Coelom Sponges Specialized cells for feeding, p g reproduction water out glassy structural elements ameboid cell central cavity pore semifluid matrix flattened surface cells collar cell water in water in But not luffa sponges these are actually fruits from a member of the cucumber family flagellum collar of microvilli nucleus Why is Sponge Bob Squarepants not really a sponge? Invertebrates No Symmetry, No Coelom Radial Symmetry, No Coelom Cnidarians: Jellyfish Hydra Sea Anemone Coral (Hint: Sym...) 3 Stinging cells called nematocysts Invertebrates No Symmetry, No Coelom Radial Symmetry, No Coelom capsule's trigger (modified cilium) ) barbs on discharged thread exposed Bilateral symmetry, No coelom (acoelomate): Platyhelminthes lid Flatworms f -li i Fl t freefree living Tapeworms - parasitic barbed thread in capsule Nematocyst (capsule at free surface of epidermal cell) branching gut rudimentary brain (pair of large ganglia in head) ovary testis oviduct pharynx; h protrudes onto food, then retracts into the body between feedings pair of nerve cords that have lateral branchings genital pore Fig. 23-13, p.368 4 Rover ingests fleas Rover passes tapeworm segments Dog g Tapeworm life cycle Tapeworm Tapeworm eggs hatch eaten by flea larvae Tapeworm segments mixed with flea "dirt" Invertebrates No Symmetry, No Coelom Radial Symmetry, No Coelom Bilateral Symmetry, No Coelom Roundworms (Nematodes) C. elegans freefree-living soil nematode Genome sequenced Used in genetic, toxicological experiments Only 959 cells in body Bilateral Symmetry PseudoPseudoCoelom: Aschelminthes Roundworms (Nematodes) FreeFree-living and parasitic Why should you not eat undercooked pork? Trichinella spiralis Live roundworms from human stomach cause stomach pain, vomiting, appendicitis Elephantiasis from an infection by roundworm Wuchereria bancrofti 5 Parasitic nematode life cycle (Wuchereria bancrofti causes elephantiasis) Trichinella spiralis Live roundworms from human stomach cause stomach pain, vomiting, appendicitis Elephantiasis from an infection by roundworm Wuchereria bancrofti Invertebrates No Symmetry, No Coelom Radial Symmetry, No Coelom Bilateral Symmetry, No Coelom Bilateral Symmetry - Pseudo Coelom Bilateral Symmetry - True Coelom: Mollusks snails, clams, squid, octopus, sea slugs (nudibranchs) The Jewel Shell (relative of clams and oysters) Squid Nudibranch or Sea Slug 6 Invertebrates No Symmetry, No Coelom Radial Symmetry, No Coelom Bilateral Symmetry, No Coelom Bilateral Symmetry - Pseudo Coelom y y Bilateral Symmetry - True Coelom Mollusks (snails, clams, squid) Annelids (segmented worms) Invertebrates No Symmetry, No Coelom Radial Symmetry, No Coelom Bilateral Symmetry, No Coelom Bilateral Symmetry - Pseudo Coelom Bilateral Symmetry - True Coelom Mollusks (snails, clams, squid) Annelids (segmented worms) Insects, Spiders, And Crustaceans (c. Univ. California, Berkeley) Arthropods (crabs, spiders, insects) How many insects are there? Your textbook says that there are over 1,000,000 species Others say 5-10 million 5The hi h t estimate i 50 million! Th highest ti t is illi ! 7 Invertebrates Bilateral Symmetry - True Coelom Mollusks (snails, clams, squid) Annelids (segmented worms) Arthropods (crabs, spiders, insects) Echinoderms (sea urchins, starfish, sea cucumbers) Chordates: animals with a notochord Charaterized by "tube feet" Chordates: animals with a notochord Invertebrate Chordates Lancelets, tunicates (sea squirts) Adult Tunicates or Sea Squirts Larva nerve cord pharynx with gill slits gut pharynx with gill slits notochord 8 Somewhere in between: Braincase but no backbone Hagfish Vertebrates: Animals with a backbone Fig. 24-5, p.387 Vertebrate Chordates Fish - 21,000 species Vertebrate Chordates Fish - 21,000 species Amphibians - 4,000 species Frogs, salamanders, newts g , , Jawless fishes Cartilaginous fishes Bony fishes 9 What's happening to amphibians (populations and individuals)? Habitat destruction Increased UV light Pesticides and chemicals Parasites Vertebrate Chordates Fish - 21,000 species Amphibians - 4,000 species Frogs, salamanders, newts Reptiles 7,000 species lizards, turtles, snakes, crocodiles and alligators Vertebrate Chordates Fish - 21,000 species Amphibians - 4,000 species Frogs, salamanders, newts Reptiles 7,000 species lizards, turtles, snakes, crocodiles and alligators Vertebrate Chordates Fish - 21,000 species Amphibians - 4,000 species Frogs, salamanders, newts Reptiles 7 000 species 7,000 lizards, turtles, snakes, crocodiles and alligators Birds 9,000 species Birds 9,000 species Mammals 4,500 species How many vertebrates are there? 21,000 species of fish p p 4,000 species of amphibians 7,000 species of reptiles 9,000 species of birds 4,500 species of mammals 45,500 species of vertebrates Have all the mammals on Earth been found and described? 10 ...
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