Zoology Final

• Chondrichthyes - sharks, rays and chimera
• Chondrichthyes has a large oily liver for bouyancy
• Sharks and rays have unique teeth and gill slits
• Spiracles of Chondrichthyes - respitory water enters through the spiracles to prevent clogging, remnants of gills slits
• Heterocercal tail of chrondrichthyes efficient swimming for predators
• Placoid scales creates a tough and leather like skin
• Male chrondrichthyes have claspers for internal fertilization
• Some Chondrichthyes are oviparous some are ovovivipourous
• Mermaids purse is an egg casing in oviparous chrondrichthyes
• Ampullae in chrondrichthyes act as electroreceptors for hunting
• Nares of chrondrichthyes powerful smell
• Lateral line of Chondrichthyes senses vibrations in the water to hunt
• Ostiechthyes are bony fish
• Two types of Osteichthyes 1. Actinoptergii 2. Sarcopterygii
• telosts- modern fishes
• Actinoptergii - ray finned fish includes telosts
• Sarcopterygii - lobe finned fish includes lungfish
• Bony fish features?

  1. Operculum with one gill slit
  2. Swim bladder
  3. Homocercal caudal fin
  4. Thin and flat sides