Phylum Chordata
Characteristics of Phylum
Chordata
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Dorsal nototchord- becomes vertebrae
of spine
Dorsal tubular nerve cord
Pharangeal
pouches
7 Classes in Phylum
Chordata
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Agnatha- jawless fish
Osteichthyes- bony fish
Chondrichthyes- cartilage fish
Amphibians- frogs
Reptiles- snake, crocodile
Birds (Aves)
Mammals
Support

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Endoskeleton
Advantage- freedom
of movement
2 Major Divisions of
skeleton
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Axial- skull, spinal
column, ribs
Appendicular- pelvic
and pectoral girdle,
appendages
Circulatory Systemclosed
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Arteries- Carry blood
away from heart to
organs
Capillaries- branch off
arteries
Veins- Carry blood from
organs to heart
Nutrition in Chordates
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Carnivoresmeat eaters
Herbivoresplant eaters
Omnivores- eat
both meat and
plants
Reproduction in Chordata
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External- eggs layed, then fertilized
Internal-
Methods of Development
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Oviparous- egg laying
Viviparous- live birth
Ovoviparous- internal eggs that hatch
and are born alive
Nervous System with Brain
and Nerves
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Olfactory lobe- smell
Optic- eyesight
Cerebrum- voluntary
muscle
Cerebellum- muscle and
some involutary
Medulla Oblongataimpulses along spine
Body Heat Regulation

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Endothermic- warm blooded- birds and
mammals
Exothermic- cold blooded- fish, reptiles
and amphibians
Behavior
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Inborn (innate)- reflex, instinct
Conditioned behavior (learned)- tricks
Intelligence- can manipulate
environment and communication
Vertebrate Digestion
Vertebrate Circulation
Vertebrate Respiration
The Fish
Three Classes of Fish
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Agnatha- jawless fish
Chondrichthyes- cartilage fish
Osteichthyes- bony fish
Agnatha
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Jawless Fish
Round sucker mouth
Parasite
Lamprey, hagfish
Invasive species
Osteichthyes- Bony Fish
Chondrichthyes- Cartilage
Fish

Sharks, rays
Fish have two-chambered
heart
Fish breathe through Gills
Some fish have a Swim
bladder (airbladder)

Enables fish to maintain
depth without swimming
Sharks do not have swim bladders
How far will a pet
lover go?
Countershadingcamouflage
Lateral Line- detects
vibrations
Olfactory Lobe
Pronounced
Amphibians
“Double Life”
Metamorphosis- tadpole
to frog
Smooth, moist skin- up to 25%
of daily O2 & CO2 exchanged
with environment
3-chambered heart
Hibernation -cold weather
Estivation- hot, dry weather
External fertilization- egg
laid in or near water
Respiration by gills,
lungs, skin
Examples- frogs, toads,
salamanders, newts
Reptiles
Three chambered heart (except
for alligators and crocs)
Skin-cold, dry leatheryscales
Ectothermic- heat from
outside
Basking
Tough Flexible Shellleathery
Examples: snakes,
lizards, turtles, alligators
Snakes
Jacobsen organ- tongue
smells air
Pits- sense heat
No external ears- sense
vibrations
Kills prey by constricting,
poisoning, swallowing
whole
Hemotoxin- brakes down blood
Neurotoxins- attack nerves
Most deaths worldwide
Most dangerous and
widely spread in us
Turtles and Tortoises
Carapace and Plastron
Outside
Inside
Turtles and Terrapinswater
Tortoises
Alligators and Crocodiles
Oviparous
4-chambered heart
Who’s eating who?
13 ft Python tried to eat a 6 ft. alligator
9/26/05 Everglades