A mode of cell commitment in which the blastomere inherits a determinant, usually a set of transcription factors from the egg cytoplasm, and these transcription factors regulate gene expression to direct the cell into a particular path of development, termed as

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#Question id: 2654

#SCPH06 I Botany

Regulation of the lac operon can be envisioned as regulation of enzyme synthesis by its

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#Question id: 2642

#SCPH01 Biochemistry

We know that lactose has a positive impact on the activity of the lac operon. Tryptophan’s presence has a ________________

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#Question id: 16128

#SCPH06 I Botany

You are studying regulation of the yeast enzyme glutamine synthetase (GS), which is encoded by the GLN1 gene. You have isolated two mutants, designated gln2– and gln3–, that give decreased GS activity. Mating of either gln2– or gln3– haploids to wild type produces heterozygous diploids that show normal amounts of GS expression. When you cross either a gln2– or gln3– haploid to a gln1– strain the resulting diploids show normal expression of GS. 

Next, you decide to evaluate the promoter for the GLN1 gene. To do this you first fuse the promoter region to the LacZ coding sequence and then place this hybrid gene on an appropriate yeast plasmid. You find that cells carrying the hybrid gene express activity under the same conditions that GS is expressed in wild type cells, meaning that the promoter region you have selected contains all of the necessary cis-acting sequences for normal regulation. The figure below shows the effect of different 50 bp deletions in the promoter region on the amount of ß-galactosidase activity expressed by the reporter gene. how would you expect a gln2– gln3– double mutant to behave?

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#Question id: 5048

#SCPH01 Biochemistry

when a cell or tissue is capable of differentiating autonomously even when placed into another region of the embryo or a cluster of differently specified cells in a petri dish. This cell or tissue said to be-

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#Question id: 19306

#SCPH01 Biochemistry

35S promoter sequence is derived from which plant virus