3 public questions tagged with this topic.
Actinomorphic flowers have radial symmetry, meaning they can be divided into equal halves in multiple planes.
Ref: NCERT Class 11 Biology Chapter 5: Morphology of Flowering Plants Flower - Symmetry Aestivation Androecium Gynoecium Placentation
Cruciferae synonym Brassicaceae mustard family exhibits cruciform corolla derived Greek crux cross, four free petals arranged orthogonal in cross, four sepals decussate, six stamens tetradynamous arrangement four long medial two short lateral, superior ovary with parietal placentation and false septum replum dividing ovary forming siliqua or silicula fruit containing glucosinolates pungent defence. Fabaceae banner wings keel papilionaceous, Solanaceae gamopetalous rotate pentamerous, Rosaceae hypanthium five petals numerous stamens. Cross arrangement linked to specialized pollination by short-tongued bees flies; thus petal number arrangement easily distinguishes mustards in field during spring.
Ref: NCERT Class 11 Biology, Chapter 5: Brassicaceae cruciform corolla tetradynamous stamens siliqua
Perianth segments termed tepals when calyx corolla differentiation absent, showing similar pigmentation, size and texture throughout, often both petaloid or sepaloid without clear distinction. Condition common in monocots Liliaceae where outer whorl not green sepaloid but showy, termed petaloid tepals, or in basal angiosperms like tulip, Magnolia where gradual transition from bracts to perianth evident morphologically. Sepals and petals indistinct genetically due to overlapping B-class MADS-box gene expression domain expansion. Presence only petals still corolla, only sepals calyx, absence achlamydeous, whereas tepal concept indicates undifferentiated perianth evolutionarily intermediate.
Ref: NCERT Class 11 Biology, Chapter 5: Perianth differentiation tepals monocot characteristic
