BIO (PLANT KINGDOM).pptx i hope you will understand it

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1. PTERIDOPHYTES What are pteridophytes ? Pteridophytes are green plants with roots, stems, and leaves. They have vascular tissue and reproduce by spores, not seeds. Example: ferns and horsetails.

2. Uses: - Medical purposes,soil binders ornamental plants etc . Habitat: - cool damp shady places though some may flourish well in sandy soil conditions.

3. Sporophyte: - is the spore producing generation in the life cycle of pteridophytes . Differentiation:- is differentiated into true roots, stems and leaves. True roots:- that anchor the plant and absorb water and nutrients. Stems:- provide support for the plant and facilitates the transport of water and nutrients. Leaves:- the primary sites for photosynthesis, the process by which plants convert light energy into chemical energy. PRODUCTION

4. Sporophylls :- these are modified leaves that evolves to bear sporangia. Storbili /cones: - When sporophylls are grouped together in a compact, cone like structure its called a stobilius or cone.

5. Homosporous and Heterosporous In most pteridophytes , all the spores are the same kind ,these are called homosporous Heterospory is the production of two different types of spores by a plant: Micro spores – small spores that grow into male gametophytes Mega spores – large spores that grow into female gametophytes Genera like selaginella and salivinia which produce two kind of spores, macro and micro spores which then develops into a young embryo that takes place within the femal gametophytes and so is called seed habit (MOST IMPORTANT STEP IN EVOLUTION)