Search for dissertations about: "Donglei Chen"

Found 1 swedish dissertation containing the words Donglei Chen.

2. 1. The Origin of Tooth Replacement : Three-dimensional Synchrotron Histology Visualizes the Dental Development of Silurian Stem Osteichthyans

   Author : Donglei Chen; Per Ahlberg; Zerina Johanson; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES;

   Abstract : Mechanisms of tooth replacement distribute incongruently among extant gnathostomes (jawed vertebrates): a permanent tooth-generating dental lamina exists in chondrichthyans (cartilaginous fish) and tetrapods but not teleosts, whereas tooth shedding by basal hard tissue resorption occurs in tetrapods and teleosts but not chondrichthyans. Theories about the evolution of tooth development have been biased towards the chondrichthyan conveyor-belt replacement, since there has been no fossil evidence for the origin of osteichthyan (bony fish and tetrapods) tooth replacement until now. READ MORE