Lifeline Week 12 Follow Along Sheet
Chordates to Vertebrates
Phylum Hemichordata
- Burrowing worms that possess a _________________.
- Type of body cavity: _______________
- Possess ______________ and ________________.
What are Chordates?
- Symmetry: _______________
- Deuterostomes
- Four Characteristics:
1)
2)
3)
4)
Notochord
- Develops from _____________.
- Firm structure for skeletal support.
- Provides support to the ______________________.
- Becomes _____________ and intervertebral discs in humans.
Dorsal Hollow Nerve Cord
- Develops from _____________.
- Develops into the brain and spinal cord: the __________ ___________ ___________.
- Connects the brain to lateral muscles/organs.
- For invertebrates, nerve cord is usually _________and _________.
Pharyngeal Slits
- Connects the ____________ to the outside of the neck.
- In invertebrate chordates: ____________________________.
- In vertebrates it becomes part of the ___________ for ____________.
- In tetrapods the slits are _____________ and the remaining tissues become part of ears and head.
Post Anal Tail
- Extension past the anal region.
- Contains skeletal and muscle elements; aid in ______________.
Humans have tails!
Phylum Chordata:
- Subphylum ________________: tunicates, sea squirts, larvaceans
- Subphylum Cephalochordata: ______________.
- Subphylum Vertebrata:
1) Agnatha
2) Gnathostomes: 3 Classes: ______________,______________, ______________
Are all chordates vertebrates? Circle: YES NO
Are all vertebrates chordates? Circle: YES NO
Subphylum Urochordata:
- Larval stage: Free living and contains all 4 chordate characteristics
- Adult: sessile; retains only _____________, loss of ______________.
- Endostyle: Groove in _____________, uses mucus to gather food.
- ____________ circulatory system. _____________ digestive system.
- Tunic made of _____________ (protein).
Subphylum Cephalochordata (Lancelets):
- Both larval and adult contain all 4 chordate characteristics.
- Borrows into the sand and ____________ _____________.
- Reduced ____________, muscle derived from mesoderm called
_____________.
Complete digestive system, closed circulatory system
Vertebrate Origins:
- Theory A: Ancestral vertebrate resembled _____________.
- Theory B: Ancestral vertebrate resembled _____________.
Subphylum Vertebrata:
Agnatha (Jawless Fishes):
Hagfishes:
- _____________ retained, skull present, no _______________.
- Protection by ________________________.
- Cartilaginous skeleton, no eyes, no larval stages
Lampreys:
- ____________ living lineage of vertebrates, live in marine and freshwater.
- Larval stage: __________________. Adult stage: _____________,
feed off host blood.
Gnathostomes (Jaw Mouth):
- Jaw evolved from skeletal rods between ________________ _________ ____________.
- ______________ forebrain, enhances smell and vision.
- Paired fins and tail
- Classes:
1)
2)
3)
Subclass ________________ and ________________
Class Chondrichthyes (Cartilagenous Fishes)
- Sharks, rays, and their relatives.
- Skeleton made of _____________, sometimes infused with____________.
- Most are carnivores, some filter feeders.
- ___________________: Detect electric fields generated by _________________ of other animals.
- Lateral Lines: Detect _____________ and _______________.
Sharks:
- ____________ scales: increase hydrodynamics
- ______ - chambered heart
- Buoyancy: ________ in liver
Rays:
- Mostly ___________ dwellers; feed on mollusks and crustaceans
- Enlarged ___________ ___________: propel through water
- Long tail can sometimes be venomous.
Class Osteichthyes (Bony Fishes)
- Ossified ______________ with hard matrix made of ____________ ________________.
- Gill cover: _______________
- Buoyancy: ________________
Subclass Sarcopterygii:
- ___________ finned fishes.
- Pectoral and pelvic fins resemble __________.
- Actinista: _____________, considered living fossils.
- Dipnoi: _______________, swim bladder used for gas exchange when pond dries.
Subclass Actinopterygii:
- __________ finned fishes, bony ray supports fin.
- _____ chambered heart
- Posses swim bladder, live in marine and freshwater
- Includes ________, clownfish, seahorses