7 public questions tagged with this topic.
George Bentham and Joseph Dalton Hooker proposed the natural classification system for flowering plants, considering both external and internal features.
Ref: NCERT Class 11 Biology Chapter 3: Plant Kingdom Angiosperms and Plant Life Cycles - Alternation of Generations
Basal placentation is found in sunflower, not in hibiscus. Hibiscus has axile placentation.
Ref: NCERT Class 11 Biology chapter - Morphology of flowering plants
Angiosperm carpel interpreted as conduplicate megasporophyll whose margins fuse enclosing ovules borne on placenta within ovary cavity, providing protection and selective pollen tube competition. Post-fertilization ovary wall differentiates into pericarp: exocarp, mesocarp, endocarp contributing fruit diversity dehiscent or indehiscent, fleshy or dry, adaptations for dispersal by animals zoochory, wind anemochory or water hydrochory. Gymnosperm ovules attached exposed on ovuliferous scales lack ovarian enclosure, seeds remain naked with no pericarp, only seed coat derived from integuments. Integument forms seed coat not fruit, while sporophyll term applies broadly, carpel enclosure remains definitive diagnostic angiosperm innovation enabling coevolution with frugivores.
Ref: NCERT Class 11 Biology, Chapter 5: Morphology, carpel ovary fruit enclosure angiosperms
Although flower and fruit traditionally considered hallmarks, homoplasious structures exist: Gnetum produces bisexual strobili resembling flower with perianth-like bracts, some gymnosperm seeds develop fleshy sarcotesta mimicking fruit, vessel elements evolved convergently in Gnetales and angiosperms. Most unambiguous embryological evidence remains double fertilization producing embryo plus triploid endosperm via triple fusion, observed in all Angiospermae after careful microscopy requiring clearing techniques. Trait couples nutritive tissue formation to fertilization event, economizing resources and enabling imprinting parental conflict. Enclosed carpel forming ovary complements but fertilization biology provides mechanistic, phylogenetically conserved criterion separating flowering plants from gymnosperms in modern systematics.
Ref: Campbell Biology, 12th ed., Chapter 30: Angiosperm synapomorphies double fertilization diagnostic
Correct option is B, Sunflower. In PHOTOPERIODISM problems like this, the accurate statement is Sunflower; the others are common mix-ups. Not these: A) Rice; C) Wheat; D) Barley. Tissue transport questions usually turn on xylem vs phloem, living vs dead cells, or source vs sink.
Ref: Best CSIR NET Plant Physiology books: Master Unit 6 with Taiz & Zeiger and Salisbury & Ross. Crack Part C experimental questions with top textbooks.
Correct option is B, Vessels. In BASICS of PLANT problems like this, the accurate statement is Vessels; the others are common mix-ups. Not these: A) Tracheids; C) Fibers; D) Parenchyma. Tissue transport questions usually turn on xylem vs phloem, living vs dead cells, or source vs sink.
Ref: Best CSIR NET Plant Physiology books: Master Unit 6 with Taiz & Zeiger and Salisbury & Ross. Crack Part C experimental questions with top textbooks.
