lecture 6

Question 1

elasmobranchii

Answer 1

-cartilagenous skeleton, no ribs
-placoid scales
ex: tiger shark, basking shark
-5-7 gill slits
-ovoviparous mostly

Question 1

Holocephali

Answer 1

-ex: ratfish, elephant fish
-cartilagenous skeleton
-upper jaw fused to skull (autostylic)
-large grinding tooth plates
-electrorecpetors
-internal fertilization, oviparous

Question 2

3 elasmobranchii respirations

Answer 2

1. buccal pumping: pushes water over gills
2. spiracle: draws water in over gills
3. ram ventilation: constant swimming