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Consider the segment polarity genes.  If the reciprocal signaling center between the engrailed (En) and wingless (Wg) expressing cells is disrupted (e.g., by a loss-of-function mutation in hedgehog), what is the immediate expected consequence for the En expression stripe?

A C. elegans mutant has a mutation in LIN-12/Notch that prevents its cleavage by the protease that acts in this pathway. The vulva cells in these mutants would likely develop with three primary (1˚) cell fates and no secondary (2˚) cell fates.

If a C. elegans hermaphrodite is heterozygous for a null (no activity) mutation in a maternal effect lethal gene, what percentage of its progeny embryos will die?

You have identified a new Drosophila segmentation gene that is expressed in a seven stripe pattern in the late syncytial blastoderm stage. A. To which class of patterning gene does your new gene likely belong? B. If your hypothesis is correct, what general phenotype are you likely to observe if you inactivate this gene?

Which one of the following statements about early Drosophila development is true?

You have identified a new pair rule Gene in Drosophila. The best way to begin to understand its regulation by gap genes would be to:

Which option below best describes the output from the following program. #include int main(){   int x, y, z=5;   for (x=10; x3; y–)           z += (x+y); printf(“%d”,z);   return 0;}

A burn that is red but does not blister is classified as:

Which of these foods do not yield dietary fiber?

Which factor accounts for the most variation in meeting a child’s total caloric needs?