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TLS Online TPP Program

#Question id: 15817

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?

#SCPH12 I Genetics
  1. Seven
  2. Two
  3. Four
  4. Five
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TLS Online TPP Program

#Question id: 92

#SCPH05 I Biotechnology

Monosaccharide derivatives in which an amino group replaces one of the hydroxyl groups may have important roles in
TLS Online TPP Program

#Question id: 13090

#SCPH06 I Botany

To express a yeast gene in E. coli, your task is to design a strategy to insert the yeast gene into the bacterial plasmid. Below is a map of the area of the yeast genome surrounding the gene in which you are interested.

 
The distance between each tick mark placed on the line above is 100 bases in length
Below are the enzymes you can use, with their specific cut sites shown 5’-XXXXXX-3’ 3’-XXXXXX-5’

 
The plasmid is 5,000 bases long and the two farthest restriction enzyme sites are 200 bases apart. The plasmid has an ampicillin resistance gene somewhere on the plasmid distal from the restriction cut sites.
                              
You do the digestion of the insert and the vector and then ligate the two digestions together. You then transform the ligation into bacteria and select for ampicillin resistance. You get three colonies on your transformation plate. You isolate plasmid from each one and cut each plasmid with the enzyme XbaI. You then run your three digestions on an agarose gel and see the following patterns of bands. Describe what each plasmid actually was that was contained in each of the three colonies.
 
What is the Colony 3’s plasmid is;
TLS Online TPP Program

#Question id: 16322

#SCPH28 | Zoology

Immediately after putting on a shirt, your skin might feel itchy. However, this perception soon fades due to ________.
TLS Online TPP Program

#Question id: 10518

#SCPH05 I Biotechnology

HC-toxin from the fungus Cochliobolus carbonum, which causes northern leaf blight disease, and inhibits
TLS Online TPP Program

#Question id: 4940

#SCPH28 | Zoology

In their laboratory simulations of the early Earth, Miller and Urey observed the abiotic synthesis of