Concept explainers
a.
To determine:
The conclusion that can be drawn by the results obtained from mating mutant strains with wild-type strains of Neurospora.
Introduction:
In Neurospora, after meiosis, the four meiotic products undergo subsequent mitosis to produce eight spores in the ascus.
b.
To determine:
The conclusions that can be drawn by the results obtained from mating mutant strains.
Introduction:
Assume that the three mutant strains are referred to as trp1, trp2, and trp3. In each haploid strain of Neurospora, one mutant trp-
c.
To determine:
The number of PD, NPD, and T out of 100 octads.
Introduction:
The tetrad that has the parental configuration of alleles is known as parental ditype (PD). Nonparental ditype (NPD) contains four recombinant spores, two of each type. Tetratype (T) contains four different spores, two spores are recombinants, and two are parental.
d.
To draw:
The genetic map that can provide a suitable explaination for the given data.
Introduction:
The cross between trp1 and trp2 can be represented as follows:
e.
To determine:
The reason that the given case does not present the mating in the table as ordered octads.
Introduction:
First-division (MI) and second-division segregation pattern are the types of segregation pattern for each gene that can be seen by the ordered octads.
f.
To determine:
The reason that the distance between gene and centromere can be observed from crosses given in the table.
Introduction:
SCO (single crossover) refers to the meiosis that takes place with a single crossover between a particular gene pair.
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Genetics: From Genes to Genomes
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