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Deuterostomes Notochord Dorsal, hollow nerve cord Pharyngeal gill slits
Muscular Postanal tail
Phylum: Chordata Phylum: Chordata
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Notochord: long flexible rod between gut and nerve cord– Present in all embryos– Fluid-filled cells in
fibrous tissue– Length of animal,
‘skeleton’
Phylum: ChordataPhylum: Chordata
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Dorsal, hollow nerve cord– Ectoderm, rolls into tube– Becomes central nervous system– Inverts have ventral,
solid cords
Phylum: ChordataPhylum: Chordata
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Pharyngeal gill slits– Filter feeders (?)– Modified for gas exchange
Muscular Post-anal tail– Skeletal and
muscular; Propulsion– Digestive system
extends length of non-chordates
Phylum: ChordataPhylum: Chordata
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TaxonomyTaxonomy Domain – EukaryaDomain – Eukarya
– Kingdom – AnimaliaKingdom – Animalia Phylum – ChordataPhylum – Chordata
–Subphylum: Urochordata – ‘sea squirts’Subphylum: Urochordata – ‘sea squirts’–Subphylum: Cephalochordata - lanceletsSubphylum: Cephalochordata - lancelets–Subphylum: VertebrataSubphylum: Vertebrata
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Phylum: ChordataPhylum: ChordataSubphylum: Urochordata
Tunicates; Sea squirts Marine, sessile Larva are free swimming;
(have all characteristics)
Larva Adult
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Phylum: ChordataPhylum: ChordataSubphylum: CephalochordataSubphylum: Cephalochordata
Lancelets Bladelike Marine Burrow into sand Filter feeders
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Phylum: ChordataPhylum: Chordata
Subphylum - VertebrataSubphylum - Vertebrata HagfishesHagfishes - jawless marine fish
– Cartilaginous skull and axial rod of cartilage derived from the notochord
– Lack vertebrae
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Phylum: ChordataPhylum: ChordataSubphylum: Vertebrata Subphylum: Vertebrata
Phylum: Chordata: Phylum: Chordata: – NotochordNotochord– Dorsal, hollow nerve cordDorsal, hollow nerve cord– Pharyngeal gill slitsPharyngeal gill slits– Post anal tailPost anal tail
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TaxonomyTaxonomy Domain – EukaryaDomain – Eukarya
– Kingdom – AnimaliaKingdom – Animalia Phylum – ChordataPhylum – Chordata
–Subphylum: VertebrataSubphylum: Vertebrata Class Agnatha – Jawless fishClass Agnatha – Jawless fish Class Chondrichthyes – cartilage fishClass Chondrichthyes – cartilage fish Class Osteithyes – bony fishClass Osteithyes – bony fish Class Amphibia – amphibiansClass Amphibia – amphibians Class Reptilia – reptilesClass Reptilia – reptiles Class Aves – birdsClass Aves – birds Class Mammalia Class Mammalia
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Vertebrates Vertebrates
5 basic groups:5 basic groups:– FishFish– AmphibiansAmphibians– ReptilesReptiles– BirdsBirds– Mammals Mammals
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Fish Characteristics Fish Characteristics Aquatic; gills for respiration Sexes separate; internal and external
fertilization– Oviparous – lay eggs (Nemo)– Ovoviviparous – eggs remain in body until
hatched (sea horses, some sharks) Two chambered heartheart Ectotherms (‘cold-blooded’) – body
temperature matches environment Most covered in scales
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Fish Fish
3 types:3 types:– Agnatha – jawlessAgnatha – jawless– CartilaginousCartilaginous– Bony Bony
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Class: Agnatha Lamprey eelsLamprey eels
– Ectoparasites Ectoparasites Scaleless Scaleless OviparousOviparous Anadromous or freshwaterAnadromous or freshwater Edible – no bonesEdible – no bones
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Class: Chondrichthyes Class: Chondrichthyes
Cartilaginous fish - harks, rays, skatesCartilaginous fish - harks, rays, skates Jaws, teeth of bone; skeleton of cartilageJaws, teeth of bone; skeleton of cartilage
– Flexible, fast, agileFlexible, fast, agile Sexes separate; fertilization is internalSexes separate; fertilization is internal Almost all marine (bull shark, ray)Almost all marine (bull shark, ray) Covered in placoid scales (‘dental ridge’)Covered in placoid scales (‘dental ridge’)
– More efficient, quieter swimmersMore efficient, quieter swimmers
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Class: Chondrichthyes Class: Chondrichthyes Predators/scavengersPredators/scavengers Excellent senses:Excellent senses:
– SmellSmell– Lateral line system – changes in water Lateral line system – changes in water
pressure caused by vibrations in waterpressure caused by vibrations in water– Electrosensors on noseElectrosensors on nose
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Rays, skatesRays, skates Dorso-ventrally flattenedDorso-ventrally flattened Bottom dwellersBottom dwellers Crush molluscsCrush molluscs Whiplike tail, barbWhiplike tail, barb
Class: ChondrichthyesClass: Chondrichthyes
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Skate or Ray?Skate or Ray? Skates – ‘mermaid’s purse’, Skates – ‘mermaid’s purse’,
sharp teeth; fat, fleshy tail sharp teeth; fat, fleshy tail with no barbwith no barb
Rays – viviparous; flat, crushing teeth, long, Rays – viviparous; flat, crushing teeth, long, whip-like tail with barbswhip-like tail with barbs
Body shapeBody shape
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Sharks Sharks 440 species440 species Carnivores, some filter feedersCarnivores, some filter feeders Liver for buoyancy Liver for buoyancy
– Not efficient so must keep movingNot efficient so must keep moving
Ram ventilation – force fresh water over Ram ventilation – force fresh water over their gillstheir gills
Oviparous, ovoviviparous, viviparousOviparous, ovoviviparous, viviparous Pelagic, coastal, bottom dwellersPelagic, coastal, bottom dwellers
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Class: Osteichthyes Class: Osteichthyes
Skeleton is bone; calcium phosphate Marine, freshwater Operculum – bony plate covering gills
– Protection– Pumps water over gills; without moving
Swim bladder – gas-filled sac (buoyant) 2 pairs of paired appendages
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Osteichthyes Osteichthyes Scales (exceptions) Ectotherms (tuna, swordfish) Carnivores, herbivores,
omnivores Teeth Dioecious External and internal fertilization Oviparous and ovoviviparous Mating, territoriality behaviors
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Cold blood from the gills is passed near warmer blood from
internal muscles; slow exchange of heat to
colder blood. Fish are much more active in colder waters. 10-20
body lengths/sec
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Osteichthyes Osteichthyes
2 types:– Actinopterygii - ray-finned – ‘rays’ of thin
bone in fins
– Sarcopterygii - lung fish, Coelocanths
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Class: AmphibiaClass: Amphibia
“dual life” Metamorphosis – egg, tadpole, adult
– Aquatic then terrestrial– Algae then predators– Eggs in water– Adults on land (mostly)– Gills to lungs/skin– Lateral line to eardrum
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Amphibians Three chambered heart Ectotherms Smooth skin – diffusion of
oxygen Many retain gills as adults Near or in water; moist soil,
burrows High humidity; tropical rain forests 3 types: frogs/toads, salamanders, Caecilians
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Dioecious External fertilization, large numbers of
eggs Mating behaviors;
Vocalizations
Amphibians
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Amphibia Amphibia
Caecilians, ‘blind lizard’ legless, almost blindCaecilians, ‘blind lizard’ legless, almost blind Burrow in soft mud, tropicalBurrow in soft mud, tropical
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Class ReptiliaClass Reptilia Poikilothermic, ectothermsPoikilothermic, ectotherms
– Lower caloric intake, Lower caloric intake, – Less active, ambush predatorsLess active, ambush predators
3-chambered heart 3-chambered heart Scales; keratin (protein)Scales; keratin (protein) LungsLungs Carnivores, herbivores, omnivoresCarnivores, herbivores, omnivores
Subphylum: VertebrataSubphylum: Vertebrata
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Class: Reptilia• Dioecious; internal fertilization, cloaca Oviparous, ovoviviparous, viviparous Amniotic Egg;
– Amniotic fluid and shell
– Prevents desiccation; lay eggs on land
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Class: Reptilia
4 Orders:4 Orders:– Testudines – turtlesTestudines – turtles– Squamata – lizards and snakesSquamata – lizards and snakes– Sphenodontia – tuataraSphenodontia – tuatara– Crocodalia - ?Crocodalia - ?
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Class: ReptiliaClass: Reptilia
Order: TestudinesOrder: Testudines Turtles, tortoises, terrapinsTurtles, tortoises, terrapins Omnivores, no teeth Omnivores, no teeth MigrationMigration Marine, fresh, terrestrialMarine, fresh, terrestrial Internal fertilizationInternal fertilization Oviparous – on landOviparous – on land
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Order Squamata Lizards, snakes Carnivores, herbivores External ear Heat sensing organs
Class: ReptiliaClass: Reptilia
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Class: ReptiliaClass: Reptilia
Order: CrocodaliaOrder: Crocodalia EctothermsEctotherms 4-chambered heart4-chambered heart Parental careParental care
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Hearts: Vertebrates Have Excellent Hearts: Vertebrates Have Excellent Closed Circulatory SystemsClosed Circulatory Systems
2–chambered 2–chambered
3-chambered3-chambered
4-chambered 4-chambered
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Vertebrate HeartsVertebrate Hearts
2 chambered2 chambered– Fish (Agnatha, Fish (Agnatha,
Chondrichthyes, Chondrichthyes, Osteichthyes)Osteichthyes)
– Oxygenated blood goes Oxygenated blood goes directly to tissues without directly to tissues without returning to heart returning to heart
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Vertebrate HeartsVertebrate Hearts 3 chambered3 chambered:
– Amphibians, reptiles– Oxygenated blood and
deoxygenated blood can mix
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Vertebrate HeartsVertebrate Hearts 4 chambered4 chambered:
– Birds, mammalsBirds, mammals– Oxygenated blood is Oxygenated blood is
separated from separated from deoxygenated blood (more deoxygenated blood (more efficient gas exchange)efficient gas exchange)
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Birds Birds
EndothermsEndotherms 4-chambered heart4-chambered heart FeathersFeathers
– FlightFlight Increased surface area Foil
– Camouflage – Mate attraction– Insulation
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Flight Flight Feathers
– Increase surface area without increasing weight– Create a foil shape (lift)
Strong wing muscles– Highly oxygenated– Large keel for attachment of muscle
Hollow bones - decrease weight Parabronchi – ‘lung’ ’ spread throughout body Reduced body parts
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Sternum, Keel; large surface area for
attachment of flight muscles
Surface area
Hollow bones
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Bird CharacteristicsBird Characteristics
Scaly legs – reptiles?Scaly legs – reptiles? Keratin beak – no teeth (weight)Keratin beak – no teeth (weight) Dioecious; dimorphicDioecious; dimorphic Oviparous – amniotic eggOviparous – amniotic egg Most have high parental careMost have high parental care
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MammalsMammals
Endotherms 4-chambered heart Fur/hair – most (bristles) Mammary glands – milk Dioecious; dimorphic 3 3 basic types: monotremes, marsupials,
placentals
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Class: Mammalia - MonotremesClass: Mammalia - Monotremes
Duck-billed platypus, spiny echidnaDuck-billed platypus, spiny echidna Oviparous Oviparous No nipples – patches on skin, milk ‘oozes’ outNo nipples – patches on skin, milk ‘oozes’ out Cloaca Cloaca
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Mammals: Marsupials
Pouched - marsupium Viviparous Young born very altricial (helpless) Climb into pouch attach to nipple and suckle
to fuller development Most in Australia; opposum
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Class: Mammalia - PlacentalsClass: Mammalia - Placentals
ViviparousViviparous Young develop attached to mother’s body Young develop attached to mother’s body
via a placentavia a placenta– Nutrient/waste exchange ONutrient/waste exchange O22, sugar, sugar
– Surrounded by amnion Surrounded by amnion
Most commonMost common