STUDY GUIDE FOR EXAM 1
- Be familiar with the types
of characteristics that make an organism ideal for the study of
- Know the critical
contributions of the sperm and the egg to the zygote.
- Know the mechanism of the
acrosomal reaction in sea urchin sperm. Understand its function.
- Know the mechanisms
responsible for the fast block and slow block to polyspermy during
fertilization in sea urchins.
- Be able to draw the first
four rounds of cell division of the sea urchin embryo. Understand how the planes of cell
division relate to cell fate specification. Be able to label macromeres, mesomeres, and micromeres
and know which cell types are derived from each of these cell layers in
the early embryo.
- Be familiar with the stages
and cellular mechanisms (ingression, invagination, convergent extension)
of gastrulation in the sea urchin.
- Understand the difference
between specification and determination. Be able to describe experiments that would help you
distinguish between when a cell has become specified and when its fate has
- Know the difference between
autonomous versus conditional modes of specification. Be able to provide examples of
- Be able to categorize
experiments (both classical and modern) into “SHOW IT”,
“BLOCK IT”, AND “MOVE IT” categories. Understand how “SHOW
IT” experiments can establish correlations, whereas the other two
can help establish causation.
Be able to distinguish between experiments that show necessity and
those that show sufficiency.
- Be able to design a set of
experiments that will demonstrate whether a proposed factor is both
necessary and sufficient to cause a developmental event.