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B250 Biology of Development    2001

 

 

ANSWER FOUR QUESTIONS in THREE HOURS

 

 

1.  How has the study of Drosophila segmentation helped us understand patterning of the vertebrate neural tube?

 

2.  Outline the principles of how axons find their targets during nervous system development, and describe EITHER formation of the retino-tectal map OR how commissural axon pathways are established in the ventral neural tube.

 

3.  Write an essay on branching morphogenesis.

 

4.  Describe the genetics of the Bithorax Complex (BX‑C) of Drosophila and explain how the Lewis model can be reconciled with the known arrangement of genes.

 

5.  Write an essay on sex determination in mammals.

 

6.  Describe how the embryonic axes of the amphibian embryo are established by maternal gene products.

 

7.  Write an essay on gametogenesis and fertilization.

 

8.  Describe pre-implantation development of the mouse.  Explain how embryonic stem (ES) cells are derived and how they can be used to manipulate gene expression in mice.

 

 

END OF PAPER

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