Bread mold can grow in a minimal medium without supplements (wild type) while certain mutated strains (mutants) can only grow in a minimal medium that is supplemented with specific intermediates found in the following metabolic pathway for arginine synthesis:

minimal ------> ornithine -------> citrulline ------> arginine, where enzyme 1 converts the precursor to ornithine, enzyme 2 converts ornithine to citrulline, and enzyme 3 converts citrulline to arginine.
A strain that can grow in a minimal medium containing arginine, but NOT in a minimal medium containing citrulline or ornithine would have a mutation in the gene that encodes for
A. enzyme 1.
B. enzyme 2.
C. enzyme 3.
D. both enzymes 1 and 3.
E. both enzymes 2 and 3.


C. enzyme 3.

Biology & Microbiology

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Fill in the blank with the appropriate word.

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Answer the following statement true (T) or false (F)

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