A lysine-requiring, proline-requiring strain of Neurospora crassa was crossed to

Question

A lysine-requiring, proline-requiring strain of Neurospora crassa was crossed to a normal, prototrophic strain. An unordered tetrad analysis was performed. Assume that the lysine gene is centromere linked and that the proline gene is 10 cM away from its centromere on a non-homologous chromosome. A. What types of cultures would be produced from the ascospores in a PD ascus, an NPD ascus, and a TT ascus? B. How many TT asci would be found out of 100 asci scored? How many PD and NPD asci would be found among the remaining asci?

Explanation / Answer

A critical abundance of PD over NPD quadruplicates demonstrates linkage of two markers. The guide separations were figured by the recipe

delineate = 50 (T 4-6NPD)/(PD 4-NPD - 1-T).

This equation considers just single and twofold hybrids between two markers, therefore prompting a think little of guide separations at whatever point the division of quadruplicates with in excess of two recombination occasions achieves an obvious level. This will be the situation if NPD quadruplicates surpass, say, 5%.

Mating write is controlled by a solitary combine of alleles that show 4:4 isolation among unordered asci which were shot from the perithecia. The guide indicates loci whose request is built up with sensible assurance. Request of markers in brackets is dubious. The centromere is spoken to as a circle. The request of qualities recorded underneath the guide is less settled in respect to loci appeared on the guide; rates and portions show recombination among arbitrary ascospore offspring, unless expressed generally

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.