FISH

1
FISH

• AGNATHA - JAWLESS FISH
• CHONDRICHTHYES - CARTILAGE FISH
• OSTEICHTHYES - BONY FISH

2
AGNATHA

• Example lamprey, hagfish
• Jaw-less, round mouth fish
• Habitat - freshwater, marine
• Integument - skin w/ mucus
• Body shape - snake like
• Caudal fin only appendage
• Cartilage skeleton, retain notochord

3
AGNATHA

• Lamprey - parasite hagfish - scavenger
• Gills w/ open gill slits
• Closed circulation w/ 2 heart chambers and single
  loop
• Ectothermic body temp
• Excretion - kidneys, dilute ammonia
• Brain w/ dorsal nerve cord
• Separate sexes w/ external fertilization

4
CHONDRICHTHYES

• Example shark, ray, skate
• Habitat - marine
• Integument - placoid scales embedded in skin
• Body shapes open water - streamlined
• bottom dweller -
  flattened
• Appendages paired and unpaired fins,
• powerful asymmetrical
  tail fin

5
CHONDRICHTHYES

• Cartilage endoskeleton
• Powerful jaws w/ rows of replaceable teeth
• Predators
• Gills w/ open gill slits
• Closed circulation w/ 2 heart chambers and single
  loop
• Ectothermic body temp
• Excretion kidneys, dilute ammonia

6
CHONDRICHTHYES

• Brain w/ dorsal nerve cord, highly developed
  olfactory lobes
• Highly developed senses - smell, vibrations,
  electromagnetic sense
• Separate sexes w/ some internal fertilization and
  some external fertilization
• No swim bladder

7
OSTEICHTHYES

• Example bass, perch, crappie, catfish
• Habitat - freshwater, marine
• Integument - skin mucus,
• overlapping scales
  mucus
• Streamlined body shape
• Appendages - paired and unpaired fins,
• highly maneuverable and
  
• symmetrical tail fin

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OSTEICHTHYES

• Jaws w/ teeth
• Variety of diets - h, c, o, s
• Small and large intestine
• Gills covered by an operculum
• Closed circulation w/ 2 heart chambers and single
  loop
• Ectothermic body temp

9
OSTEICHTHYES

• Excretion - kidneys, dilute ammonia
• Brain w/ dorsal nerve cord, highly developed
  olfactory lobes
• Well developed sense of smell
• Lateral line to detect vibrations and pressure
  changes
• Separate sexes w/ some internal fertilization but
  most external fertilization

10
OSTEICHTHYES

• Swim bladder
• Modern fish are ray finned
• Ancient fish are lobed finned
• Lobed fin lungfish considered by evolutionists to
  be ancestors of amphibians