This is a matching question. What gene or genes must be present in a floral whorl in order for a stamen to form in that whorl? What gene or genes must be missing (loss of function) from an otherwise normal plant to get a phenotype of all sepals in the flowers? Which of the floral organ identity genes did Pelaz et al engineer into plants along with a SEP gene to create petals in place of leaves ? What regulatory region would you use to localize expression of a reporter construct in the bottom two whorls of a floral meristem?.