Green and Black turtles have finely serrated jaws adapted for a vegetarian diet although they are mainly carnivorous from hatchling to juvenile size, then they become mainly herbivores.
Loggerheads' and Ridleys' jaws are adapted for crushing and grinding because their diet consists of crustaceans.
Hawksbill turtles have narrow heads with jaws meeting at an acute angle, adapted for getting food from crevices in coral reefs. They eat sponges, shrimps, and squids.
Leatherbacks have delicate scissor like jaws adapted for their diet of jellyfish and other soft-bodied animals. Their mouth cavity and throat are lined with papillae(spine like projections) to help swallow soft bodied creatures.