- Tracheids - Specialised cells for conducting water and supporting tissues (forming the xylem vessels)
- All SPOROPHYTES in this group are larger than the gametophytes and have ROOTS, STEMS AND LEAVES.
- can be further sub divided into the non- sees tracheophytes and the seed plants
THE SPERMATOPHYTA 'Seed Plants';
Now represented by two Phyla:
- The Gymnosperms:
( Cycads, Gingkos, Gneetophytes, Confiers)
- Angiosperms
(Magnoliphyta or flowering plants)
COMMON THINGS IN ALL SEED PLANTS;
- Seeds
- Reduced Gametophytes
- Heterospory: Spored of two different sizes and sexes
- Ovules: Female gametophyte, protected by tissues of sporangium
- Pollen: Male Gametes (Sperm cells)
THE ALTERNATION OF GERNERATION IN THE SPERMATOPHYTA;
- The gametophyte generation is reduced to a very small, simple stage (only a few cells!).
- The gametophyte develops partly or entirely whilst it is still nutritionally dependent on the sporophyte.
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