In the book by Bard, please read the following assignment over the weekend,
and be ready to discuss its content on Monday (continued on Wednesday and Frida7):
Chapter Five The morphogenetic properties of mesenchyme
When structure-building cells crawl around as individuals, they are called mesenchyme.
Chapter Six The epithelial repertoire pp 181-237 (for Friday)
Epithelia are stuck regularly together, in continuous sheets
The outer layer of skin is epithelial; the lining of the digestive tract is epithelial;
the wall of the blasocoel is an epithelium.
Preface 2 pages
p. 1 intro definition approach
no single underlying theme, just a lot of mechanisms? And species?
p. 5 the plan 5 sections
Chapter two background; history
Every object has a shape. Some forces must have caused that shape.
Humans cut materials, boards for example, to create arbitrary shapes.
Animal shapes, cell shapes, bone shapes, tooth shapes etc. are caused by genes.
Embryology is partly about the forces that arrange cells, and shape cells so that they will have the correct anatomical shapes and structure.
When you watch an embryo develop, the shape changes you see are caused by various physical forces:
Cell contractions, water pressure (in the blastocoel, for example), osmotic swelling of cartilage
p. 15 footnote: an aspect to experimental embryology; it needs ideas, and almost any idea will do so long as it is experimentally disprovable.
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