pedicellate teeth

Examples of pedicellate teeth in the following topics:

• Characteristics and Evolution of Amphibians

  • Additional characteristics of amphibians include pedicellate teeth (teeth in which the root and crown are calcified, separated by a zone of noncalcified tissue) and a papilla amphibiorum and papilla basilaris (structures of the inner ear that are sensitive to frequencies below and above 10,00 hertz, respectively).

• Ingestion

  • The first step to obtaining nutrition is ingestion, a process where food is taken in through the mouth and broken down by teeth and saliva.
  • Once in the mouth, the teeth, saliva, and tongue play important roles in mastication (preparing the food into bolus).

• Characteristics of Mammals

  • Most mammals have heterodont teeth, meaning that they have different types and shapes of teeth rather than just one type and shape of tooth.
  • Most mammals are diphyodonts, meaning that they have two sets of teeth in their lifetime: deciduous, or "baby" teeth, and permanent teeth.
  • Other vertebrates are polyphyodonts: their teeth are replaced throughout their entire life.

• Digestive System: Mouth and Stomach

  • The food is broken into smaller particles by mastication, the chewing action of the teeth.
  • All mammals have teeth and can chew their food.
  • The chewing and wetting action provided by the teeth and saliva shape the food into a mass called the bolus for swallowing.
  • Food is masticated by teeth and moistened by saliva secreted from the (b) salivary glands.

• Classification of Joints on the Basis of Structure and Function

  • Gomphoses occur between teeth and their sockets; the term refers to the way the tooth fits into the socket like a peg .

• The Fossil Record as Evidence for Evolution

  • Fossils usually consist of the portion of the organisms that was partially mineralized during life, such as the bones and teeth of vertebrates or the chitinous or calcareous exoskeletons of invertebrates.
  • This approach is most successful for organisms that had hard body parts, such as shells, bones or teeth.

• Vertebrate Digestive Systems

  • The teeth play an important role in masticating (chewing) or physically breaking down food into smaller particles.
  • They do not have teeth, so their digestive system must be able to process un-masticated food .
  • An interesting feature of the ruminants' mouth is that they do not have upper incisor teeth.
  • They use their lower teeth, tongue, and lips to tear and chew their food.

• Evolution of Mammals

  • Eutherians are distinguished from noneutherians by various features of the feet, ankles, jaws, and teeth.
  • Most study of the evolution of mammals centers, rather, around the shapes of the teeth, the hardest parts of the tetrapod body.
  • The later synapsids, which had more-evolved characteristics unique to mammals, possess cheeks for holding food and heterodont teeth (specialized for chewing by mechanically breaking down food to speed digestion and releasing the energy needed to produce heat).

• Human Axial Skeleton

  • In animals with teeth, the mandible brings the surfaces of the teeth in contact with the maxillary teeth.

• Gnathostomes: Jawed Fishes

  • Most sharks are carnivores that feed on live prey, either swallowing it whole or using their jaws and teeth to tear it into smaller pieces.
  • Shark teeth probably evolved from the jagged scales that cover their skin called placoid scales.