PHYLUM CHORDATA
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Transcript of PHYLUM CHORDATA
PHYLUM CHORDATAPHYLUM CHORDATA
Phylum Chordata CharacteristicsAll chordates at some
point in their life cycle have:
-dorsal hollow nerve cord (just above the notochord)
-notochord (Strong, Strong, flexible, rodlike structure flexible, rodlike structure called a called a notochordnotochord at some at some point in their lives usually point in their lives usually replaced by a backbone in replaced by a backbone in adults))adults))
-pharyngeal pouches
-tail extending beyond the anus
-bilateral symmetry
Invertebrate ancestor
Phylogeny of ChordatesPhylogeny of Chordates
Phylum ChordataPhylum Chordata
Divided into 3 subphylum:Divided into 3 subphylum: Subphylum Vertebrata Subphylum Vertebrata
• VertebratesVertebrates Subphylum TunicataSubphylum Tunicata
• Tunicates, ex. Sea squirtsTunicates, ex. Sea squirts Subphylum CephalochordataSubphylum Cephalochordata
• Lancelets – small fish-like creatures that live at the Lancelets – small fish-like creatures that live at the bottom of the oceanbottom of the ocean
Phylum ChordataSubphylum: Vertebrata
-About 96% of chordate species are vertebrates.
-Vertebrates have a strong supporting structure called the backbone, made of segments called vertebrae. Besides support, the backbone protects the spinal cord.
-The top of the spinal cord grows into a brain.
- Have a skull that protects the brain
- Vertebrates have an endoskeleton made of living cells that grows with the organism (internal skeleton made of cartilage and bone)
7 Classes of Subphylum 7 Classes of Subphylum Vertebrata:Vertebrata:
1.1. Class Agnatha [Class Agnatha [ag-nuh-thuh]ag-nuh-thuh] – jawless fish ex: – jawless fish ex: lamprey *minimal skeleton only a few cartilage plateslamprey *minimal skeleton only a few cartilage plates
2.2. Class Chondrichthyes (con-drik-thee-eez]Class Chondrichthyes (con-drik-thee-eez] – – cartilage fish ex: shark *entire skeleton is cartilagecartilage fish ex: shark *entire skeleton is cartilage
3.3. Class Osteichthyes Class Osteichthyes [os-tee-ik-thee-eez][os-tee-ik-thee-eez] – bony fish – bony fish *most fish belong to this group and their skeleton is *most fish belong to this group and their skeleton is made largely of bonemade largely of bone
4.4. Class Amphibia Class Amphibia [am-fib-ee-uh][am-fib-ee-uh] – amphibians ex: – amphibians ex: frogs *most have an aquatic larval stagefrogs *most have an aquatic larval stage
5.5. Class Reptilia Class Reptilia [rep-til-ee-uh][rep-til-ee-uh] – reptiles ex: snakes – reptiles ex: snakes *reproduce on land*reproduce on land
6.6. Class Aves Class Aves [ey-veez][ey-veez] – birds *have feathers and fly – birds *have feathers and fly7.7. Class MammaliaClass Mammalia [ma-ma-leea][ma-ma-leea] – mammals *hair or – mammals *hair or
fur and develop internally and nurse off milk after birthfur and develop internally and nurse off milk after birth
Fish Agnatha: jawless fish
Chondrichthyes: cartilage fish
Osteichthyes: Bony fish
AmphibiansFrogsToadsNewts
SalamandersCaecilians
ReptilesSnakes
Lizards
Crocodilians
Turtles
Tortoises
Tuatara
Aves:The Birds
Mammalia: the mammals
•These animals have no backbone, but do have a notochord.
•Also have a dorsal hollow nerve cord, pharyngeal pouches and a tail.
•Soft bodied marine organisms
•Although very different from vertebrates, they are distant relatives
Subphylum Tunicata / Subphylum Cephalochordata Subphylum Tunicata / Subphylum Cephalochordata (Nonvertebrate Chordates)
Urochordata: The Tunicates -Filter-feeders (larval
and adult)
-Name comes from the tough covering called a tunic
-Called sea squirts
-Larvae have all four chordate characteristics
-Adult tunicates have no notochord or tail
Tunicate Larva
-Notochord
-Hollow dorsal nerve cord
-Pharyngeal pouches
-Tail
Cephalochordata: Lancelets
- Small fish-like animals that live in the sandy bottom.
-Have a head region with a mouth.-Lancelets take water into their pharynx and pick out food.
-Pharynx has up to 100 pairs of gill slits
-Have a circulatory system but no heart. Blood is moved by the vessels.