PTERIDOPHYTES
Lifecycle of Pteridophytes
Ferns and other vascular plants are mainly found in the stage of a sporophyte. Underneath the fronds of the sporophytes are small containers called sporangia. There sporphytes develope haploid spores through meiosis. A group of sporangia is called sori. Once those spores are released and found a good spot to germinate, it grows first some root-like rhizoids. Then it flattens into a greeen structure which is the haploid mature gametohpyte which grows independently of the sprophyte. The female archegonia and the male antheridia are found on the underside of the gametophyte. Through a thin film of water the sperm, produced in the antheridium, swims over to the archegonia to fertilize its egg and to build a diploid zygote. This diploid zygote develops into a new sporophyte plant through mitosis. As the sporophyte grows, the gametophyte withers away.
Examples of Pteridophytes
Horsetail
Fern
Psilotum
Selaginella
Bryophytes and Pteridophytes - Comparison and Contrast
Pteridophytes
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Both
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Bryophytes
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Vascular tissues in Pteridophytes
Vascular tissues are the "transport tubes" of a plant. They conduct water through the 'xylem' from the roots to the leaves and nutrients (from photosynthesis) from the leaves to the roots (or basically everywhere were the plant has to grow). Vascular tissues are useful for the plant as structural support. The further conduction of nutrients and water also allows the plant to grow larger.
The Gametophyte Generation
Pteridophytes spend the largest amount of therif lifecycle in the state of the sporophyte. Before, they are in the haploid gametophyte stage which is called 'Prothallus' for a fern. This gametophyte is really small and produced the gametes for the later fertilizaion to build the sporophyte. Pteridophytes are homospory which means that they have the female and the male gametophyes on the same plant.
The Sporophyte Generation
In the state of a sporophyte, pteridophytes have vascular tissues in their stems but lack them in their hyphae or fronds ('leaves'- but never call them leaves). They sty in that state for the most time of its life which is a big difference between bryophytes and pteridophytes.