You and your lab partner have isolated 20 new mutant yeast strains that are defective in synthesis of threonine, an amino acid. These Thr- mutants do not grow on minimal medium, but they do grow on minimal medium supplemented with threonine. Ten of your Thr- mutants (numbered 1 through 10) were isolated in a strain of mating type a (MAT a). The other 10 Thrmutants (numbered 11 through 20) were isolated in a strain of mating type α (MAT α). You and your lab partner cross each of the MAT a strains to each of the MAT α strains, and you include crosses to the appropriate wild-type strains. Your experimental observations are shown in the table below, where (-) indicates diploids that did not grow on minimal medium and (+) indicates diploids that did grow on minimal medium

Based on these experiments, what is the minimum number of genes required for threonine synthesis?

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#Question id: 15422

#Unit 5. Developmental Biology

During Vulval induction in C. elegans, the anchor cell secretes, a paracrine factor which receives by VPCs and become vulva. If the anchor cell is destroyed, the VPCs will not form a vulva. This is the example of:

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#Question id: 15738

#Unit 5. Developmental Biology

In humans and many other mammals, the sex chromosomes are called:

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#Question id: 15739

#Unit 5. Developmental Biology

 In mammals, If no Y chromosome is present then transcription factors Wt1, Lhx9, GATA4, and Sf1 activate expression of:

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#Question id: 15740

#Unit 5. Developmental Biology

The position of the testis-determining gene was narrowed down to a 35,000-base-pair region of the:

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#Question id: 15741

#Unit 5. Developmental Biology

The region of the Y chromosome have a male-specific DNA sequence that encodes a peptide of 223 amino acids. This gene is called:

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#Question id: 15742

#Unit 5. Developmental Biology

Which of the following  hormone enables the development of the Müllerian duct into the uterus, oviducts, cervix, and upper portion of the vagina?