Govt Exams
Cycas is a cycad and belongs to the order Cycadales, which are living fossils representing ancient gymnosperms.
Gymnosperms have naked seeds not enclosed in an ovary. Seeds enclosed in an ovary is a characteristic of angiosperms.
Pteridophytes possess both xylem (for water conduction) and phloem (for nutrient transport), but lack the specialized sieve tubes and companion cells found in angiosperms.
Megasporophyll is the structure bearing megasporangia; in angiosperms, it corresponds to the carpel which produces megaspores.
Ferns possess true vascular tissue (xylem and phloem) and have a dominant independent sporophyte generation, making them more advanced than bryophytes.
Rhizoids are root-like structures that anchor bryophytes to the substrate and facilitate absorption of water and minerals.
Mosses exhibit alternation of generations with the gametophyte (haploid) being the dominant, photosynthetic generation, while sporophyte is dependent.
Bryophytes lack true roots, stems, and vascular tissue, while pteridophytes possess true vascular tissue (xylem and phloem) and roots.
Flowers and fruits are the most recent evolutionary advancements (approximately 140-150 million years ago), making angiosperms the most evolved plants.
Spores are haploid products of meiosis; seeds contain a diploid embryo, endosperm, and seed coat. Seeds are more advanced structures for dispersal.