What is a tooth?
A: A tooth is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food.
The roots of teeth are covered by what?
Teeth are not made of bone, but rather of multiple
tissues of varying density and hardness that originate from where?
A: The embryonic germ layer, the ectoderm.
he general structure of teeth is similar across the
vertebrates, although there is considerable variation in their what?
A: Form and position.
The teeth of mammals have deep what?
This pattern is also found in some fish, and in what?
In most teleost fish, however, the teeth are attached
A: To the outer surface of the bone.
In lizards they are attached to what?
A: The inner surface of the jaw by one side.
In cartilaginous fish, such as sharks, how are the
A: By tough ligaments to the hoops of cartilage that form the jaw.
Monophyodonts are animals that develop only one what?
A: Set of teeth.
Diphyodonts have an early set of deciduous teeth and a
later set of what?
A: Permanent or "adult" teeth.
Polyphyodonts develop many sets like Sharks who grow a
new set of teeth how often?
A: Every two weeks to replace worn teeth.
Rodent incisors grow and wear away continually through
A: Gnawing, which helps maintain relatively constant length.
In many reptiles and fish, teeth are attached to what?
A: The palate or to the floor of the mouth.
Some teleosts even have teeth in what?
A: The pharynx.
Teeth appear to have first evolved in what animals?
The shape of the animal's teeth are related to its
In dogs, the teeth are less likely than humans to form
dental cavities because of what?
A: The very high pH of dog saliva, which prevents enamel from demineralizing.
An adult horse has how many teeth?
A: Between 36 and 44.
Horse teeth can be used to estimate the animal's what?
Elephants' tusks are specialized incisors for doing
A: Digging food up and fighting.