Practical 3 Flashcards
What is homodont dentition?
It’s where all teeth in the jaw are alike.
Common in reptiles
What is heterdont dentition?
Differentiation of teeth within the jaw for specialized functions. Common in mammals.
In which direction does a carnivore’s jaw move?
Jaw moves in an up and down motion
In carnivores, where do molars first meet?
Molars meet at the back first then gradually move towards the front
How many blades are on a cheetah’s tooth?
Each tooth has one or two blades
In which direction does and Koala’s (leaves-browsing) jaw move?
Jaw moves up and down at the start then moves in a side-to-side motion
In koalas, where do molars first meet?
Molars meet at the same time
In which motion does a horse’s (grass-grazer) jaw move?
Side-to-side grinding motion
Dentition types for molars:
Tribosphenic Myrmecopahous Sectorial Homodont Bunodont Lophodont Seledont Filter feeder
Tribosphenic
A triangular-shaped tooth with three peaks used to pierce invertebrate exoskeletons (e.g., shrew, bat)
Animals with tribosphenic molars generally have what type of gut?
Short/medium length, with a simple gut
Myrmecopahous
Dentition is characterized by a reduction in size, complexity, and amount of enamel present. Extreme development of this trend is the total loss of teeth e.g. echidna
Do platypus’s have teeth?
They do not, use a keratin plate instead to grind their food
What type of gut do animals with Myrmecopahous teeth generally have?
Short, simple gut
Sectorial
A tall, blade-like tooth, overlapping with its opposite tooth when the jaw is closed thus providing a shearing force e.g., cats and dogs
how do sectorail teeth differ from tribosphenic teeth in function?
Sectorial teeth are used more for slicing than piercing
What gut would you expect animals with sectorial molars to possess?
Short and simple gut
Homodont
All the teeth are similar in size and shape and very simple e.g., seal, dolphin
How do homodont teeth differ from sectorial teeth in function?
Homodont teeth are used for catching and grasping fast-moving food rather than slicing off flesh
What type of gut would you expect animals with homodont teeth to possess?
Long and simple gut
Bunodont
Roughly square or oval in outline, with low, rounded cusps e.g., humans, pigs, bears
What is the order of the mouth for animals with bunodont teeth?
Long sharp teeth at the front to rip and cut, with grinding molars at the back to break down plant material
What gut type would you expect from animals with bunodont teeth?
Medium length to simple/complex guts
Lophodont
Enamel ridges run across the tooth surface e.g., elephants, kangaroos
