In maize, one allele of a particular gene allows chlorophyll production while the other allele prevents this, giving plants with cream coloured leaves. Half the seeds from a cross between two green-leaved plants were sown in trays kept in the dark. The other half were sown in similar conditions except that they received light. The table gives the results obtained. What was the number of green-leaved plants formed from seeds germinating in the dark? [Figure 40.1]

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