Phylum Chordata

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Phylum Chordata 3 Subphyla ‘URO-CEPHALO-VERT’ Subphylum Urochordata Subphylum Cephalochordata Subphylum Vertebrata Adult Has only 1 Chordate characteristic: Pharyngeal gill bars have become a filter feeding basket Subphylum Urochordata Larva Has all 4 Chordate characteristics Subphylum Urochordata Tunicate tadpole larvae Note 4 chordate characteristics: 1. Dorsal hollow nerve cord 2. Notochord 3. Pharyngeal gill slits or bars A 4. Post-anal tail (A) Subphylum Cephalochordata Post anal tail Notochord Nerve cord Anus Atriopore Pharyngeal gill Cirri Metapleural Folds bars & slits Phylum A Chordata Subphylum Cephalochordata B C B D Dorsal region Note: fin ray (A), myomeres (B), dorsal hollow nerve cord (nerve tube) (C), notochord (D) B P. gill bar O Ovary B O C P gill slit C B D A B Phylum C Chordata Subphylum B C Cephalochordata E Endostyl MF e MF Anterior region Note: (D) pharynx, (E) endostyle – (produces mucus to help catch food in between the gill bars - Yummy!) (MF) - Meta pleural folds (A) atrium Phylum Chordata Subphylum Vertebrata 7 Classes - Agnatha Hagfish & Lampreys Chondrichthyes Sharks Osteichthyes Bony fish Amphibia Frogs & Salamanders Reptilia Turtles & Crocs Aves Birds Mammalia Your lab partner! Phylum Chordata Subphylum Vertebrata TYPES of SKELETON Cartilaginous Skeleton (2 classes) Agnatha Chondrichthyes Bony Skeleton (5 classes) Osteichthyes ‘RAAMO’ Amphibia Reptilia Aves Mammalia Phylum Chordata Subphylum Vertebrata NUMBER OF HEART CHAMBERS Agnatha 2 Chondrichthyes Osteichthyes Amphibia 3 Reptilia (except crocs) Crocs 4 Aves Mammalia Phylum Chordata Subphylum Vertebrata WHO HAS AN AMNIOTIC EGG? Amniotes – ‘RAM’ Reptilia Aves Mammalia Phylum Chordata Subphylum Vertebrata Always take the shortest route…… If you can’t remember all the classes that are ectothermic… just remember those that aren’t! Endothermic Aves Mammalia Endothermy – ability to maintain body temperature by internal metabolic processes Don’t forget the dissections……. and all those special little structures.

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