Phylum Chordata and Fishes Flashcards
5 main characteristics of Phylum Chordata
notochord, nerve cord, pharyngeal pouches/slits, endostyle/thyroid glands. postanal tail
notochord function
flexible rod of cartilage or bone that supports animal’s back
nerve cord function
connection between brain and nerves
pharyngeal pouches/slits function
in the throat area, generally disappear before birth
endostyle/thyroid gland function
secretes hormones
ectotherms
cold blooded: don’t produce much internal body heat, body temp changes with surroundings
endotherms
warm blooded: produce internal body heat and maintain constant body temp, can live in a greater variety of environments
ectotherm examples
fish, amphibians, reptiles
endotherm examples
mammals, birds
What advantages do endotherms have over ectotherms?
endotherms can live in more environments
Five main groups of vertebrates
fish, mammals, reptiles, birds, amphibians
Number of fish species
28,000 species
Percentage of fish
49%
Number of mammal species
5,400 species
Percentage of mammals
9%
Number of reptile species
8,100 species
Percentage of reptiles
14%
Number of bird species
9,700 species
Percentage of birds
17%
Number of amphibian species
6,000 species
Percentage of amphibians
10%
jawless fish classes
Myxini and Petromyzontida
Class Myxini example
hagfish
Class Petromyzontida example
lamprey
Class Myxini characteristics (5)
only live in salt water; skull, no true vertebral column, retain notochord; scavengers/predators; mostly blind with rudimentary eyespots and sensory tentacles; produce slime
Class Petromyzontida characteristics (4)
migrate from salt to fresh to spawn; larvae filter feed for 3-7 years; become parasites as adults; suction cup mouth, lined with sharp teeth to feed on blood of prey
3 classes of fish
Chondrichthyes, Sarcopterygii, Actinopterygii
Class Chondrichthyes common name
cartilage fish