If you can explain how you do these 3 questions as well I wo

If you can explain how you do these 3 questions as well I would greatly appreaciate it

1. A student is asked to characterise six yeast strains labelled 1, 2, 3, 4, 5 and 6. The student begins by streaking cells of each strain onto nine different tester media shown in Table I. Table l: Growth responses of the six strains on different tester media strain YEPD MM MM A MM L MM H MM +A L L H H H Legend growth and no growth, MM minimal medium, YEPD complete medium L leucine, A- arginine, and H histidine (each is an end product of a separate biochemical pathway, all are required for growth i) Using only the data from Table i, determine the genotype of each strain, using the same format as the wildtype strain. For this question only, assume there is only 1 gene/ pathway ie. Only 1 enzyme involved in making histindine, one enzyme to make arginine, etc. (3 pts) Strain Genotype Strain Genotype Wildtype arg leu his 6

Solution

first what is auxotroph: it is a strain which is not able to produce (for eg.) histidine on its own as it has no gene responsible for it, so there should be another source added to help this strain grow.

prototrophic: strain which is able to produce histidine on its own (wild type)

answer for que 1. following are the genotypes:

1. arg^- , leu^- , his^- as it is able to grow on minimal media supplemented with all the 3 ( external source is required for growth)

2. his^- as it grows when the media is supplemented with histidine

3. arg^- as it grows when the media is supplemented with arginine

4. arg^- leu^- both as it requires both for its growth

5. leu^- as it grows when the media is supplemented with leucine

6. arg^- as it grows when the media is supplemented with arginine

answer for