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e) The organizer secretes factors that activate
formation of the Nieuwkoop center. Understanding embryonic development
In general, cells become more restricted in
their developmental potential as embryonic
development proceeds. This progessive determination involves first
combinatorial control by transcription factors,
but later gene silencing by epigenetic changes
in DNA and chromatin. 3 12/2/12 Understanding embryonic development
Sheets of cells (epithelia) can rearrange to
change shape and move
e.g. convergent extension Cells in an epithelium can leave it and become
mesenchymal. Mesenchymal cells can join an
e.g. during gastrulation. Which of the following is NOT true of the
a. Induces gastrulation
b. Inhibits ventral ectoderm
c. Converts ventral mesoderm to intermediate
d. Involutes through the dorsal lip of the blastopore
e. Becomes intermediate mesoderm Transplant purple cells Patterns of cells with different fates and
behaviors can arise in response to gradients
of diffusible signaling factors (morphogens),
and then be maintained by local cell interactions.
Morphogens can be intracellular (e.g. transcription factors in
the Drosophila syncytial blastoderm embryo), but are usually
extracellular. Again, signaling pathways, for both pattern
determination and maintenance. These cells are
purple What can you conclude about the purple...
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This note was uploaded on 01/22/2014 for the course MCB 305 taught by Professor Schroeder during the Fall '11 term at University of Arizona- Tucson.
- Fall '11