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The Francis Crick Papers

Title:
Diffusion in Embryogenesis pdf (519,479 Bytes) ocr (18,299 Bytes)
Diffusion in Embryogenesis
Description:
After fifteen years of seminal work on the structure and function of DNA and on the genetic code, Crick decided to switch to a new field, embryology or developmental biology, as it came to be called. His overall goal was to understand how genes were expressed and controlled the growth and specialization of tissues and organs. He soon became intrigued by the fact that in two-dimensional sheets of cells, such as those that form the retina of developing embryos, each cell seemed to know its location relative to the other cells in the sheet, and could send out signals that directed further growth accordingly. This phenomenon was attributed to gradients, considered to be regular changes in the concentration of a chemical (Crick called it a morphogen) across the sheet. In this article, he offered a mathematical theory for how such gradients might form through diffusion of the morphogen from a source at one end of the sheet to a "sink" that destroys the chemical at the other. This theory was independent of the fact that the biochemistry of the proposed gradients--what molecules formed which gradient--was unknown. Nor could it be determined in the years to come, prompting Crick to leave behind this field of investigation.
Item is a photocopy.
Number of Image Pages:
3 (519,479 Bytes)
Date:
1970-01-31 (January 31, 1970)
Creator:
Crick, Francis
Source:
Periodical: Crick, Francis. "Diffusion in Embryogenesis." Nature 225, (31 January 1970): 420-422. Article. 3 Images.
Publisher:
Nature Publishing Group
Rights:
Reproduced with permission of the Nature Publishing Group.
URL: http://www.nature.com/nature/index.htmlExit
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Exhibit Category:
Embryology and the Organization of DNA in Higher Organisms, 1966-1976
Unique Identifier:
SCBCCF
Document Type:
Articles
Language:
English
Format:
application/pdf
image/tif
Physical Condition:
Good
Folder: [Selected articles collected by NLM]
Metadata Last Modified Date:
2009-02-09
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