BIO
BIO200 Notes - Diversity.docx

Shed cuticles 4 times during lifetime c elegans a

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Shed cuticles 4 times during lifetime C. elegans A model organism Matures in 3 days Limited amount of cells Tardigrades or water bears Extremely small Can be dormant for long periods When water dries Last up to a decade Live in sand or water films on plants Onychophorans: Velvet worms are terrestrial and closely related to arthropods Segmented & unjointed Soft External cuticle containing chitin Internal fertilization and egg development Probably related to being exclusively terrestrial Arthropods Arachnids Mouthparts are chelicerae Four pairs of legs Myriapods Mouthparts are mandibles Bodies consist of one head, one pair of antennae and repeated segments Crustaceans Mouthparts are mandibles Two pairs of antennae Five pairs of appendages Shrimp, lobster, pill bug Insects Mouthparts are mandibles Bodies have three regions One pair of antennae Three pairs of legs Air sacs and tubes allow for gas exchange Contain most named species on earth ~2.1 million named 36% are beetles
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Arthropod means jointed feet or jointed appendages Trilobites had jointed appendages Body plans are dominated by jointed appendages Head Thorax Abdomen Have exoskeletons Grow new skeleton under the old one
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11/5/2018 -------------- Mammals Mammals likely survived the extinction of the dinosaurs due to endothermy Almost all mammals have placentas Have symbionts that allow them to digest cellulose Use keratin to develop hooves and horns Hooves lessen impact while running Some mammals can fly Bats have a leathery membrane of skin for wings Mammals are unified by five traits Hair Keep warm Camouflage Sensory Dolphins and whales have lost most hair but still have it on their snouts Defense Hedgehogs Mammary glands Leads to nipples for offspring to consume milk with high fat to develop brain Endothermy Homoplasious in mammals and birds Sweat glands Secrete liquids to cool animals Most animals have localized sweat glands Four-chambered hearts Endothermy is very energy demanding There are two groups of mammals Prototherians (Monotremes) Therians (Marsupials and Eutherians) Both show convergent traits Most species of mammals are eutherians Marsupials Often have pouches Small internal gestation Mainly in Australia and South America Eutherians Diverged quickly after the mass extinction of dinosaurs Diverged as the continents broke apart during the late Mesozoic Echidna
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Has hair = mammal Smell guides them to food Feeds on small invertebrates Doesn’t give live birth Egg inside of hair Platypus Only other mammal to lay eggs Feeds on small invertebrates Sensors in bill detect electromagnetic signals
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11/7/18 ---------- The primates lineages Primates have two traits in common Grasping fingers and toes Opposable thumbs Flattened nails to keep claws out of the way for climbing Binocular vision Forward facing eyes Produces overlapping which provides depth perception The hominidae (hominids) Comprises the great apes and humans (hominins) Strepsirrhini (wet-nosed) primates Wet-nosed
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  • Fall '18
  • jessica poulin
  • Bacteria, Flowering plant

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