Vertebrates

Vertebrate Characteristics• Endoskeleton• Vertebrae• Integument• Gills & Lungs• _____________ circulatory system• Digestive Tract• _____________ remove nitrogen waste• Brain• Sexual reproduction

Phylum Chordata

• Notochord• Dorsal hollow nerve cord• Pharyngeal pouches• Post anal tail

These are present at some time in the developmental process

General Characteristics

• Vertebral column• Cranium• Closed circulatory system• Neural crest• Internal organs• Endoskeleton

Vertebrate Classes

• Agnatha – Jawless fish• Chondrichthyes – Cartilage and unique scales• Osteichthyes – bony fish• Amphibia – double life (aquatic and land)• Reptilia – egg layers• Aves – wing • Mammalia – hair and mammary gland

Evolution of the Jaw

The Fishes• Jawless Cartilaginous Calcified Bone• Life in Water– Streamline body– Dense tail muscle– Gill lung– Swim bladder

• Homeostasis– Kidney function

• Sensory Functions– Lateral line system

AgnathaJawless fish• Lack paired fins• No plates or scales• Cartilage• No swim bladder• _______________________• Ectothermic• External fertilization• ________ chambered heart• Gills• Examples - Hagfish and Lamprey

Chondrichthyes

Cartilage skeleton ______________________ Paired fins No swim bladder Lateral line Ectothermic Internal fertilization _______ chambered heart Gills Triangular teeth Shark, Ray, Skate

Osteichthyes

Bony fish Lateral line _________ chambered heart Lung swim bladder ________________ with gills Scales Paired fins Ectothermic External fertilization Spawning Examples - Lobe and Ray fins

Amphibia Ectothermic Gills lungs ______________________

Respiration Protection

__________ chambered heart Separation of oxygenated and deoxygenated blood

Bony skeleton Digestive system External fertilization Metamorphosis

• Evolution 370 million years ago• Lobed fin moved over land• Challenges – Water availability– Air temperature– New habitats– Climate shifts

• Orders of Amphibians– Urodela – salamander

– Anura – frogs and toads

– Apoda - caecilians

Reptilia• Evolved from amphibians– Greater modifications– Cortex region of brain– ________ chambered heart w/ partial divided

ventricle• Water freedom– Water tight skin– Copulatory organ– Kidney– ___________________________

• The Amniotic Egg

• Orders– Crocodilia • Crocodile• Alligator

– Chelonia• Turtles

– Squamata• Lizards and Snakes

Aves• Evolved from ___________

– Only 150 million years ago• Horny keratinized beak, scaly

leg, egg laying• Feathers• Wing• Strong muscles• ________________________• _________ chambered heart• Endothermic• Migration

Mammalia

Origin from small, hairless reptile Traits

Increased Brain capacity _________________________ Hair Dentition for dietary habits __________ chambered heart _________________________ Endothermic

• Orders– ________________________• Duckbilled platypus• Spiny anteater

– ________________________• Pouched animals• Australia and New Zealand

– ________________________• Young nourished within uterus• placenta