Final answer:
Mutant organisms requiring pyridoxine will not grow on a minimal medium without pyridoxine, since the mutation prevents them from synthesizing pyridoxine and the medium does not provide it.
Step-by-step explanation:
Organisms or spores with a mutation resulting in the loss of function of an enzyme essential to the biosynthesis of the vitamin pyridoxine will be unable to synthesize pyridoxine on their own. As a result, these organisms will only grow in media where pyridoxine is provided. They cannot grow on minimal medium without pyridoxine, as this medium does not supply the necessary vitamin that the mutated organism can no longer produce internally.
Complete medium with pyridoxine contains all the nutrients required by Neurospora, including pyridoxine, hence organisms with this mutation can grow in it. Minimal medium with pyridoxine is a simple medium supplemented with pyridoxine, which compensates for the mutation's deficiency, enabling growth.
Complete medium without pyridoxine supplies all nutrients except pyridoxine; however, if the complete medium contains enough of precursors or related compounds that can compensate for the lack of pyridoxine, growth might be possible, depending on the specific medium composition.