Read the information below and then answer the questions that follow. In an experiment similar to those by Beadle and Tatum, Neurospora spores were mutated and grown in minimal medium test tubes. Mutants unable to grow without the amino acid "L"were isolated. Compounds A, B, and C are precursors to L. The following data are generated by providing these compounds to the mutants.
Data: All strains grow if given compound L.
Strains that grow given compound B also grow if given A or C.
Strains that grow given compound C do not grow if given only B or A.
Strains that grow given compound A will also grow if given C, but not if given only B.
-The order in which the molecules are converted in the pathway is:
A) A, C, B, L.
B) B, C, A, L.
C) C, B, A, L.
D) B, A, C, L.
E) C, A, B, L.

Question

Quizplus · Accepted Answer

The information indicates that all strains grow with L, suggesting it is the final product. Strains growing with B also grow with A or C, indicating B is upstream. Strains growing with A also grow with C but not B, placing A before C but after B. Strains growing with C and not with A or B suggest C is directly before L. Thus, the pathway is B, A, C, L.

Read the Information Below and Then Answer the Questions That