The Developmental biology reference article from the English Wikipedia on 24-Jul-2004
(provided by Fixed Reference: snapshots of Wikipedia from wikipedia.org)

Developmental biology

You can make a difference by sponsoring a child
Developmental biology is the study of the process by which organisms grow and develop. Originating in embryology, today developmental biology studies the genetic control of cell growth, differentiation and "morphogenesis," which is the process that gives rise to tissuess, organss and anatomy. The related field of evolutionary developmental biology was formed largely in the 1990s and is a synthesis of findings from molecular developmental biology and evolutionary biology which considers the diversity of organismal form in an evolutionary context.

Often used model organisms for developmental biology are the round worm Caenorhabditis elegans, the fruit fly Drosophila melanogaster, the zebrafish Brachydanio rerio, the mouse Mus musculus, and the weed Arabidopsis thaliana.

The findings of developmental biology can help to understand (or some day, cure) developmental malfunctions such as chromosomal aberration, for example, down syndrome. An understanding of the specialization of stem cells to specific tissues and organs could lead to the specific cloning of organs for medical purposes.

Table of contents
1 Molecular mechanisms of development
2 Developmental model organisms
3 External links

Molecular mechanisms of development

During the second half of the 20th century the types of molecules involved in embryonic development were identified. Transcription factors are the key regulators of which genes are expressed in cells. Transcriptional control in the various differentiated cell types allows each type of cell (epithelial, muscle, neuron, etc) to express different amounts of the possible proteins. The transcription factors are regulated by signal transduction pathways that relay signals from outside of cells to the cell nucleus. Signal transduction pathways often involve receptors, receptor ligands and enzymes such as protein kinases. One key class of genes that are differentially regulated by transcription factors in different cell types are genes for cell adhesion proteins. Cell adhesion proteins are among the key regulators of morphogenesis.

Concepts in developmental biology
allantois, amnion, blastocyst, blastomere, blastula, blastulation, chorion, chrysalis, cleavage, ectoderm, embryo, embryogenesis, embryogeny, embryology, endoderm, evocation, extra-embryonic membrane, fetus(or foetus), gastrula, gastrulation, germ layer, germ plasm, germ, germination, induction, juvenile, larva, maternal effect, mesoderm, metamorphosis, morphogenesis, morula, neoteny, neural development, nymph, ontogeny, oosperm, ovism, paedogenesis, pangenesis, phylogeny, primordium, pupa, rudiment, teratology, zygote

Developmental model organisms

Vertebrates

Invertebrates Plants

External links