Vertebrates

14-1: Chordates14-2: Fish

14-3: Amphibians

14-4: Reptiles15-1: Birds

15-2: Mammals

14-1: Chordates• animals with these characteristics

o Notochord●firm but flexible tube that extends along

upper part of bodyo Postanal tailo Nerve cordo Pharyngeal pouches

Notochord Nerve Cord

• chordates include vertebrateso have all the chordate characteristicso also have:

● Endoskeleton– internal skeleton– made of bone & cartilage

● Backbone– made of vertebrae– replaces notochord– protects spinal nerve cord

● Skull– protects brain

Vertebrae

• Vertebrates grouped based on body temperature regulationo Ectotherms

●body temperature changes with surroundings

●“cold-blooded”o Endotherms

●regulate their own body temperature; stays constant

●“warm-blooded”

• 5 groups of vertebrateso Fisho Amphibianso Reptileso Birdso Mammals

14-2: Fish• Ectotherms• Tail• Fins

o fan-like structures attached to the endoskeleton

• Scaleso hard, thin plates that

cover the skin

• well-developed sensory systemo Ex. sharks & smell

• exchange CO2 and oxygen through• adaptations for obtaining food

o teeth, beaks, electric shock, filter feeding• reproduce sexually

o some internal, some external fertilization

gills

• Different groups of fisho Jawless fisho Cartilaginous fisho Bony fish

• Jawless Fisho no jaw bones, cartilage endoskeletono round, toothed mouthso long, tube-like bodieso no scales, slimy skino Hagfish, Lampreys

• Cartilaginous Fisho cartilage endoskeletono jaw bones with well-developed teetho tiny scales, sand-papery skino Sharks, Skates, Rays

• Bony fisho largest groupo bone endoskeletono swim bladdero 3 groups

●Lobe-finned●Lungfish●Ray-finned

14-3: Amphibians

• means “double life”• ectotherms• hibernation

o during cold weather• estivation

o during hot weather

• moist, smooth skin• no scales• breathe through skin or saclike

lungs

• Amphibian reproductiono sexualo external fertilization

●female lays eggs, male releases sperm over eggs

o eggs don’t have a protective shell—require water

• Metamorphosiso changes in body formo tadpole adulto occurs in all amphibians

Groups of Amphibians• Frogs & Toads

o four legso no neck or tailo tongue attached to front of mouth

Groups of Amphibians

• Salamanders & Newtso long, slender bodieso tails

14-4: Reptiles

• ectotherms• thick, dry waterproof skin• scales• breathe with lungs

--protection and water loss

• Reproductiono internal fertilization

●male fertilizes female●female lays eggs

o amniotic eggs● covered with shell &

contain everything needed for development

Groups of Reptiles

• Lizards & Snakeso unhinging jawso lizards have moveable eyelids & legs

with clawed toes

Groups of Reptiles

• Turtleso two-part shello no teeth

Groups of Reptiles

• Crocodilianso lizard-like in shapeo large scales on backso care for young