Hans Spemann and colleagues developed the concept of the "organizer" in amphibian embryos while studying the ________.

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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: 4907

#SCPH28 | Zoology

Two corn plants are studied. One is resistant (R) and the other is susceptible (S) to a certain pathogenic fungus. The following crosses are made, with the results shown

R male X S female = all S progeny

R female X S male = all R progeny

Which of the following are correct about inheritance?

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#Question id: 1560

#SCPH01 Biochemistry

An invertebrate, such as an insect, has innate immunity that can be nonspecific about which pathogens are prevented from harming its metabolism. Which of the following is most likely to function this way in the insectʹs intestine?

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#Question id: 10953

#SCPH28 | Zoology

What condition leads to a deficiency in factor IX that can be corrected by an intravenous injection of vitamin K?

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#Question id: 665

#SCPH01 Biochemistry

Which statement is not true about the peptide bond?