This question requires knowing the Beadle and Tatum’s experiment with Neurospora crassa and the results.
Neurospora crassa, which is a type of bread mold of the phylum Ascomycota, has provided a rich source of knowledge on “biosynthetic pathways.” Neurospora crassa was perfect substance for biosynthetic pathway experiment. Because it was cheap, easy to grow, and more importantly it is haploid for most of its life. Since Neurospora crassa is haploid, there exists only one copy of each gene so that researchers don’t need to consider about dominant and recessive alleles.
George W. Beadle(1903-1989) and Edward L. Tatum(1909-1975) made their hypothesis that if there was a one-to-one relationship between genes and specific enzymes, it should be possible to create mutants that are unable to carry out specific enzymatic reactions. They conducted experiments with Neurospora crassa since it had lots of advantages as I mentioned. For their studiy, the spores of the fungi were exposed to radiation to produce mutant varieties in DNA. And then, they crossed mutants with non-exposed molds. They found that the non-mutuated fungi could multiply in simple growth medium, and the mutated spores could not replicate in a simple growth medium. This mutated
…show more content…
the determination of the steps in a biochemical pathway. In the experiment conducted by Beadle and Tatum, they could find the biochemical reactions controlled by many genes. Hence it is correct.
B. the "one gene, one enzyme" hypothesis. It is also true. Beadle and Tatum’s experiment with Neurospora crassa proposed one gene – one enzyme hypothesis. As I mentioned above, it indicates that each mutated gene must normally dictate the production of one enzyme.
C. the idea that genes are on chromosomes. This statement is not related to the experiment with Neurospora crassa. The one who demonstrated that genes are on chromosomes is Thomas Hunt Morgan as we learned before. He is famous for experiment with fruit flies not bread