" The Big Picture!" by Mr C

Biology 11

Name: ____________________ Date: __________ Block: _____

 

Phylum Chordata

 

Human beings belong to a group of animals that all have backbones or ____________. This group is called the ____________, and is a “subphylum” of the phylum _________.

 

 

Classification of Chordates

There are 3 subphyla in phylum Chordata

1. ____________________ (uro = “__________”)
2. ____________________ (cephalo = “__________”)
3. ____________________ (vertes = “__________”)

 

The first two phyla of invertebrate chordates represent an evolutionary transition between ______________ and ______________

 

 

Four Characteristics of Chordates:

All animals in Phylum Chordata have these 4 characteristics at some point in their lives:

 

1. Most chordates have a ________________
   • the backbone evolved from the _______________ – a stiff flexible rod made of cartilage that runs along the back
   • ALL chordates have a notochord at some point during their development
   • in _______________ the notochord becomes the ________________
   • benefits of a notochord/backbone: muscles can attach to the notochord, allowing chordates to

 

2. All chordates have a ____________________
   • the nerve cord runs parallel to the _______________
   • in vertebrates this is surrounded and protected by the __________ (segments of the backbone)
   • at the ___________ end it is enlarged to form the __________

 

3. Chordates have _____________ gills
   • (pharynx = “____________”)
   • aka: ________________ (branchial = “_______”)
   • gills are used for _______________ and ______________
   • gills are supported by _____________ made of _______________
   • in embryos, gills start out as pouches in the pharynx. All ____________ have pharyngeal gill pouches at some point during their development
   • in chordates that breath water, the gill pouches become _____________ supported by__________
   • in chordates that breath air (for example _______________), the gill pouches develop into organs such as __________, and the gill arches become structures such as _______________ and ________________ (voicebox)

 

4. All chordates have a ____________________
   • the _____________________________ extend into the tail, which allows the tail to be used for ____________
   • found at some point during development in all _____________

 

 

Evolutionary Origins of Chordates:

 

The invertebrate phylum most closely related to the chordates is _________________

• Both phyla belong to a group of animals called __________________ (deutero = “_____________” and stome = “___________”)
• All other invertebrates belong to a group called __________________   (proto = “_____________”)
• The feature that Chordates and Echinoderms share is how and when their ______________ forms during embryonic development______ __________________________________

 

 

                      Protostomes                      Deuterostomes

						time

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The 2 Invertebrate Chordate Phyla

 

1. Characteristics of Urochordatata (sea squirts or tunicates)

• lifestyle: ________________________________________
• covered by a “tunic” (tunic = “__________”)
• has a _____________ but no ________________
• larva has ____________________________
• only chordate characteristic in the adult is _____________________

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2. Characteristics of Cephalochordata (lancelets)

• lifestyle: _______________________________
• retain all 4 chordate characteristics throughout life

 

 

 

 

 

 

 

 

 

 

 

3. Characteristics of Vertebrata (animals with backbones)

• in all vertebrates (except the hagfish) the notochord is replaced with a backbone made of ________________ ( = ___________________________________)
• the ___________________ is surrounded and protected by the __________
• Vertebrates also have:
  • a complex ­­­­­­­­­­­­­­­­­­_______________ and a large _______________ protected by a ________________
  • an endoskeleton with ________________ and one or two pairs of ________________
  • complex ________________
  • special ________________ (eg: skin, scales)

 

 

Vertebrate Classes

There are 7 ____________ of vertebrates

1. Agnatha – ______________________
2. Chondrichthyes – ______________________ (sharks)
3. Osteichthyes – ____________________
4. Amphibia – _____________________
5. Reptilia – __________________
6. Aves – ______________
7. Mammalia – ___________________