Phylum Chordata Invertebrate Chordates Vertebrate Chordates Trademarks of

Phylum Chordata Invertebrate Chordates Vertebrate Chordates

Trademarks of Phylum Chordata 1. • • Notochord Semi-rigid rod-like structure Present at some time during dvlpmnt. Made of cartilage Functions: 1. Stiffening 2. Axis for muscle attachment

Trademarks of Phylum Chordata 2. Hollow Dorsal Nerve Chord • Anterior end is brain • Is spinal chord in vertebrates

Trademarks of Phylum Chordata 3. Pharyngeal Gill Slits or Pouches • Location: where pharynx will be • Present at some time during life cycle

Pharynx v Pharynx

Trademarks of Phylum Chordata 4. Post – Anal Tail • Function: propulsion • Very good for swimming

Other Chordate Characteristics • Bilateral symmetry • Well- developed coelom • Ventral heart • Complete digestive tract • Endoskeleton (bone or cartilage or both)

Phylum Chordata Includes: 1. Invertebrate Chordates • Subphylum Urochordata • Subphylum Cephalochordata 2. Vertebrate Chordates • Subphylum Vertebrata

Subphylum Urochordata 1. 2. 3. 4. Tunicates and Sea Squirts Marine bottom dwellers Sessile adults with a leathery tunic Larvae possess all 4 chordate trademarks

Subphylum Urochordata • Pastel Sea Squirt

Subphylum Urochordata • Blue Bell tunicate

Subphylum Cephalochordata 1. 2. 3. 4. 5. 6. Lancelets (Amphioxus) Marine Fish-like shape, pointed at both ends Silver in color Small Closed circulatory system

Lancelet • Amphioxus