B250 exam
paper 2005
ANSWER FOUR QUESTIONS
1. Describe the structure and function of the Bithorax
and Antennapedia complexes in fruit flies. How do
they relate to the Hox gene
clusters in vertebrates?
2. Discuss the role of the Spemann
organiser in frog head development.
3. Describe the
features of pre-implantation mouse development that facilitate the derivation
of embryonic stem (ES) cells. Discuss how manipulating gene function by
homologous recombination in ES cells has added to our understanding of
vertebrate development.
4. Write an essay outlining how dorsal-ventral and
anterior-posterior patterning occur in the vertebrate central nervous system.
5. Discuss how the vasculature in vertebrates develops?
6.
Discuss the role of Pax6 as a master regulator of eye development and what
characterizes a developmental master regulator or selector gene. Explain the
structural components needed for recruiting a gene into a novel developmental pathway
during the course of evolution.
7. Discuss how limbs develop in vertebrates?
8. Answer both parts (each part is of equal
value):
a) The vasculature, the lung, and the nervous system are all branched
structures. Compare the fundamental mechanisms by which they develop. What are
the differences and what is shared? The names of individual genes are not
required but don't limit yourself just to vertebrates.
b) Compare the roles of branchless in Drosophila tracheal
development and VEGF in vertebrate vascular development.
9.
Compare
and contrast the mechanisms of sex determination in humans and Drosophila.