![]() Thus, the gametophytes that result from heterosporous plants are dioecious, either female or male. Heterosporous plants produce two types of spores - megaspores and microspores - which are female and male, respectively. Conversely, a pteridophyte that produces more than one type of spore is known as heterosporous. ![]() Unlike heterosporous plants, homosporous plants produce only one kind of spore containing both male and female parts. When a pteridophyte produces one type of spore, it is called homosporous. To start the next generation, the gametophyte, the spores are dispersed by wind or water. Pores are released from sporangia under dry conditions when the outer casing cracks and opens. A sporangium is a structure within which seed spores develop during meiosis. Such fertile fronds are called sporophylls. Sporophytes produce sporangia on the underside of fertile leaves and stems when they reach maturity. Two copies of each chromosome are found in each sporophyte cell, making it a diploid (2n) organism. Hence, all ferns growing in the forest belong to the sporophyte generation. The only generation that is noticeable is the sporophyte. The main generation is the sporophyte, which is the dominant phase. ![]() Thus, a pteridophyte plant must complete two separate generations before its life cycle is complete. Alternation of GenerationsĪ pteridophyte is like many other plants in that it undergoes alternation of generations. As we proceed through the next sections, we'll explore how pteridophytes reproduce as well as the unique structures involved. There are many similarities between the life cycle of pteridophytes and other spore-producing plants. Spores are living, single-celled structures that are vital to the life cycle of many plants. Unlike seed plants, pteridophytes do not produce cones, flowers, or fruit. The fern family, as well as its relatives, are vascular plants, but their reproduction is vastly different from the reproduction of gymnosperms and angiosperms. Differences Between Pteridophytes and Seed Plants Tree fern stem showing vascular bundles in black. Vascular bundles and vascular rings are similar to the vascular tissue organization of two angiosperm groups, monocots and dicots. Some ferns have vascular rings surrounding the pith in the stem. In other words, when viewing a cross-section of a stem, there are distinct bundles of xylem and phloem. Most Pteridophytes have bundled vascular tissue. Phloem transports nutrients like sugars and carbohydrates.The xylem transports water and minerals.When they diverged from bryophytes millions of years ago, the pteridophytes became the first group of plants to develop vascular tissue. Pteridophytes contain two kinds of vascular tissue – xylem and phloem. Tracheophytes are plants that have a vascular system that allows water and nutrients to move throughout the plant. Pteridophytes are part of a large group of plants known as tracheophytes. ![]() Their lack of seeds also distinguishes them from other vascular plants, such as gymnosperms and angiosperms. Pteridophytes are distinguished from other spore-producing plants, bryophytes, by their vascular tissue. Pteridophytes are vascular plants that produce spores, such ferns, horsetails, clubmoss, and spikemoss. Additionally, many ferns are grown as ornamentals because of their beautiful foliage. Pteridophytes are considered a class of plants that fall between bryophytes and seed plants in evolutionary terms. Ferns and their allies are found everywhere, and they are some of the most prevalent plants in certain ecosystems. Pteridophytes are ancient plants commonly called ferns or fern allies. Alternative titles: Pinophyta, Coniferophyta, Coniferae
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