How C. elegans embryos divide? What is the major issue of this paper? How C. elegans embryos divide? Whether gut differentiation is dependent on inductive signals? How to separate C. elegans blastomeres? How to observe gut differentiation Whether gut differentiation is dependent on local determinants?

What is the major approach that the author used to address his major question? Antibody staining Separation and reconstitution of blastomeres C. elegans lineage analysis Multiple approaches are used and needed. Genetic analysis

How did the author argue against the possibility that separating blastomeres from each other early in the cell cycle may damage the ability of EMS to differentiate into gut? Citing published literatures showing that this isolation procedure is safe and never affects the differentiation potential of isolated blastomeres Showing that in unoperated embryos EMS sometimes failed to differentiate into a gut Showing that damaging EMS or its neighboring blastomeres did not affect gut differentiation Putting isolated blastomeres back and showing that gut differentiated normally in all cases. The author avoided to discuss this issue

Which of the following is important for gut differentiation in C Which of the following is important for gut differentiation in C. elegans? ABa ABa + ABp ABp P2 ABp + P2

Which of the following is a correct statement? Cytoplasmic determinant is not important for gut differentiation The interaction between EMS and P2 occurs soon after cell division Recombining isolated EMS and P2 always results in gut differentiation Recombining isolated EMS and ABx always never yields correct gut differentiation All of the above

What is the most important lesson that you learn from reading this paper? It is a very cool paper Inductive signal is important for C. elegans gut differentiation One can always question existing or established dogma C. elegans is a good animal model for studying embryo development You need to have very good hands to be a good scientist