Outline7 marksChallenge
A scientist is investigating a dwarf pea mutant 'na' that overproduces DELLA protein. Normal pea plants grow tall when treated with gibberellin (GA), but the mutant remains dwarf even after GA treatment.
(a) Outline the mechanism by which gibberellin normally activates genes for stem elongation in plant cells. (b) Using the lac operon of E. coli as a comparison, describe how the gibberellin system differs in terms of: (i) the types of genes (structural vs regulatory) (ii) whether the system is inducible or repressible