During primary sex determination in mammals, the bipotential gonad is moved into the female pathway (ovary development) by the Wnt4 and Rspo1 genes, which promote accumulation of:

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#Question id: 15620

#SCPH06 I Botany

Wild type E. coli metabolizes the sugar lactose by expressing the enzyme ß-galactosidase. You have isolated a mutant that you call lac1–, which cannot synthesize ß-galactosidase and cannot grow on lactose (Lac–). During an condition Lac– strain, called lac3–, is linked to the Tn5 insertion. From a strain carrying the Tn5 insertion and lac3– mutation you isolate an F’ that caries a region of the chromosome that includes both Tn5 and the linked Lac region. Introduce this F’ into an F– strain carrying lac1– by selecting for Kanr. These merodiploids express ß-galactosidase normally. What does this result tell you about the relationship between the lac3– and lac1- mutations?  

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#Question id: 5846

#SCPH06 I Botany

The bacteriophage can lysogenize after infecting a bacterium, i.e. integrate into the host bacterial chromosome by site-specific recombination, and may reside there for many generations before an excision event regenerates the viral genome in an infective form.  Which one of the following is not a component of these events?

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#Question id: 368

#SCPH01 Biochemistry

Which of the following is true about the properties of aqueous solutions?

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#Question id: 11194

#I Life Science/ Life Sciences Group – I-V

The "threshold" potential of a membrane is the ________.

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#Question id: 18231

#SCPH06 I Botany

A DNA sample having mass 1 picogram undergoes PCR, the eluted DNA is weighted about 1 microgram, the minimum number of cycles required