Runt is a Drosophila gene involved in development. Mutation of runt leads to an embryonic lethal phenotype in which every other segment in the body plan is missing. What class of developmental genes does runt belong to? O a) Pair-rule genes O b) Segment polarity genes O c) Homeotic genes d) Gap genes

In the nematode C. elegans, some worms have blisteredcuticles due to a recessive mutation in one of the bligenes. Someone studying a suppressor mutation thatsuppressed bli-3 mutations wanted to know if it wouldalso suppress mutations in bli-4. They had a strain thatwas homozygous for this recessive suppressor mutation,and its phenotype was wild type.a. How would they determine whether this recessivesuppressor mutation would suppress mutations in bli-4?In other words, what is the genotype of the wormsrequired to answer the question?b. What cross(es) would they do to make these worms?c. What results would they expect in the F2 if(1) it did act as a suppressor of bli-4?(2) it did not act as a suppressor of bli-4?

What is the purpose of syncytin, the protein product of sequences originally added to the human genome from a retrovirus, as it relates to early fetal development in human reproduction?

According to the histone-code hypothesis, what is one way that cell specialization occurs? a) Differential DNA methylation patterns b) Variation in enhancers in different cells c) TFII transcription factors binding to different histones in a cell-specific manner d) Differential expression of histone modifying enzymes e) Different histones are expressed in different cells

Suppose that a newly identified mutation in humans causes formation of tooth tissue in the nasal cavity. What class of developmental genes would you expect to be mutated in this case? O a) Gap genes O b) Maternal-effect genes c) Pair-rule genes O d) Binary switch genes

Following a mutagenesis experiment to identify novel genes affecting the circadian clock in Drosophila melanogaster you discover several mutants. You start considering two of those mutants that you call c and d. The two homozygous c/c and d/d are arrhythmic (arrhythmic is the definition of their phenotype), whereas the two heterozygous C/c and D/d are rhythmic (rhythmic is the definition of their phenotype) with a 24h period. You make two true-breeding stocks: stock 3 homozygous for c and stock 4 homozygous for d. You cross them in both directions and in both cases you observe complementation with no difference between males and females. Then you take the progeny of one cross, for instance the F1 of Females 3 x Males 4, and you perform a Testcross. Out of 1000 flies resulting from the Testcross only 125 are rhythmic. Which is the genotype of the rhythmic flies resulting from the testcross? Select only one answer   1. C/C d/d   2. C/c D/d   3. C/c d/d   4. c/c…

It seems that developmental genetics boils down to a complex network of gene regulation. Try to draw a structure of this network for Drosophila. How many genes do you think are necessary to complete the developmental network for the fruit fly? How many genes do you think are needed for a network to specify one segment? Do you think it is more difficult to identify genes that are involved in the beginning, middle, or end of this network? Suppose you were trying to identify all of the genes needed for development in a chicken. Knowing what you know about Drosophila development, would you first try to identify genes necessary for early development, or would you begin by identifying genes involved in cell differentiation?