LAB: Craniates Part 1

Question 1

Craniates

Answer 1

• Have a cranium (skull)
• Additional Characteristics:
  
  • improved musculature
  • 2+ chambered hearts
  • Red blood cells
  • O2 transporting hemoglobin
  • kidneys

Question 2

Hagfish (Myxini)

Answer 2

• Are marine scavengers
• Produce mucus for protection
• round mouths

Question 3

​Vertebrates

Answer 3

• Craniates with vertebral column (backbone)
• most are gnathostomes (jaws)
  
  • lateral line system - pectoral, pelvic fins
  • complex brain

Question 4

Lamprey (Petromyzontida)

Answer 4

• most are parasitic as adults
• lack jaws (agnathan)

Question 5

Cartilaginous fish (Chondrichthyes)

Answer 5

• Have an endoskeleton made of cartilage
• Include:
  
  • Sharks
  • Rays
• Teeth are modified scales

Question 6

Bony Vertebrates (Osteichthyans)

Answer 6

• have an endoskeleton of ossified bone
• two groups:
  
  • Ray-finned fish
  • Lobe-finned fish

Question 7

Ray-finned fish

Answer 7

• Greatest diversity among vertebrate groups
• have fins of bony elements known as rays

Question 8

​Lobe-finned fish

Answer 8

• Thick fins
• two extant groups
  
  • Coelacanths
  • Lungfish
• 3rd group evolved into tetrapods

Question 9

Ray-Finned Fish ANATOMY

Answer 9