Assume that a series of compounds has been discovered in Neurospora.Compounds A-F appear to be intermediates in a biochemical pathway.Conversion of one intermediate to the next is controlled by enzymes that are encoded by genes.Several mutations in these genes have been identified and Neurospora strains 1-4 each contain a single mutation.Strains 1-4 are grown on minimal media supplemented with one of the compounds A-F.The ability of each strain to grow when supplemented with different compounds is shown in the table (+ = growth; o = no growth). Which biochemical pathway fits the data presented?
Media supplement
$$\begin{array} { | l | l | l | l | l | l | l | }
\hline \text { strain } & \text { A } & \text { B } & \text { C } & \text { D } & \text { E } & \text { F } \
\hline 1 & o & o & o & + & + & + \
\hline 2 & o & o & o & o & + & + \
\hline 3 & o & o & o & o & + & o \
\hline 4 & o & o & + & + & + & + \
\hline
\end{array}$$
A)A ? B ? C ? D ? E ? F
B)A ? B ? C ? F ? D ? E
C)F ? B ? C ? D ? A ? E
D)A ? B ? C ? D ? F ? E
E)A ? B ? F ? E ? C ? D

Question

Assume that a series of compounds has been discovered in Neurospora.Compounds A-F appear to be intermediates in a biochemical pathway.Conversion of one intermediate to the next is controlled by enzymes that are encoded by genes.Several mutations in these genes have been identified and Neurospora strains 1-4 each contain a single mutation.Strains 1-4 are grown on minimal media supplemented with one of the compounds A-F.The ability of each strain to grow when supplemented with different compounds is shown in the table (+ = growth; o = no growth). Which biochemical pathway fits the data presented?
Media supplement
$$\begin{array} { | l | l | l | l | l | l | l | } 
\hline \text { strain } & \text { A } & \text { B } & \text { C } & \text { D } & \text { E } & \text { F } \
\hline 1 & o & o & o & + & + & + \
\hline 2 & o & o & o & o & + & + \
\hline 3 & o & o & o & o & + & o \
\hline 4 & o & o & + & + & + & + \
\hline
\end{array}$$
A)A ? B ? C ? D ? E ? F
B)A ? B ? C ? F ? D ? E
C)F ? B ? C ? D ? A ? E
D)A ? B ? C ? D ? F ? E
E)A ? B ? F ? E ? C ? D

Quizplus · Accepted Answer

The table shows that each strain can grow when supplemented with compounds downstream of the mutation in the biochemical pathway. Strain 1 grows with D, E, and F, indicating its mutation affects the conversion of C to D. Strain 2's growth with E and F but not D suggests its mutation affects D to E conversion. Strain 3 grows only with E, indicating a mutation affecting E to F conversion. Strain 4 grows with C, D, E, and F, suggesting its mutation affects B to C conversion. This pattern fits the linear pathway A ? B ? C ? D ? F ? E.

Assume That a Series of Compounds Has Been Discovered in Neurospora.Compounds