Practice question

Pisum sativum flower demonstrates pronounced bilateral symmetry where papilionaceous corolla comprising posterior standard, two lateral wings and anterior keel can be bisected into equal halves only through median sagittal plane. This zygomorphy ensures precise bee interaction, keel must be depressed depressing diadelphous stamens to release pollen. Actinomorphic radial symmetry seen in Hibiscus and Brassica, asymmetrical in Canna, regular synonym for actinomorphic not pea. Zygomorphy in Fabaceae co-evolved with vexillary aestivation and diadelphous androecium forming tripping mechanism for specialized pollinator behaviour, representing derived floral evolution for oligolecty and efficient pollen transfer.