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HAPLONTIC HAPLO-DIPLONTIC DIPLONTIC LIFE CYCLES OF ORGANISMS A life cycle is a period involving one generation of an organism through means of reproduction, whether through asexual reproduction or sexual reproduction.
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Alternation of generations (also known as metagenesis or heterogenesis) is the type of life cycle that occurs in plants that have distinct haploid sexual and diploid asexual stages.
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are small, non-vascular plants, such as mosses, liverworts and hornworts. They play a vital role in regulating ecosystems because they provide an important buffer system for other plants, which live alongside and benefit from the water and nutrients that bryophytes collect. Bryophytes mosses liverworts hornworts
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Bryophyta The term Bryophyta came up from the word ‘Bryon’ which means mosses and phyton meaning plants. These are the plants that grow in shady and damp areas and are small in size. They lack vascular tissues. They reproduce through spores instead of producing flowers and seeds. The study of bryophytes is called Bryology.
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Why are Bryophytes Called Amphibians of Plants? Bryophytes are called “amphibians of the plant kingdom” because they’re the terrestrial plants but require water to finish their life cycle at the time of sexual reproduction.
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Classification of Bryophytes According to the newest classification, Bryophyta is split into three classes: Hepaticopsida (Liverworts) Anthocerotopsida (Hornworts) Bryopsida (Mosses)
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A pteridophyte is a vascular plant (with xylem and phloem) that disperses spores. Because pteridophytes produce neither flowers nor seeds, they are sometimes referred to as "cryptogams", meaning that their means of reproduction is hidden. Pteridophytes Ferns Club Mosses Horsetails
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Pteridophytes Pteridophytes are vascular plants and have leaves (known as fronds), roots and sometimes true stems, and tree ferns have full trunks. Examples include ferns, horsetails and club-mosses. Fronds in the largest species of ferns can reach some six metres in length! Many ferns from tropical rain forests are epiphytes, which means they only grow on other plant species; their water comes from the damp air or from rainfall running down branches and tree trunks. There are also some purely aquatic ferns such as water fern or water velvet (Salvinia molesta) and mosquito ferns (Azolla species). Pteridophytes do not have seeds or flowers either, instead they also reproduce via spores. There are around 13,000 species of Pteridophytes.
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Classification of Pteridophytes There are four classes, namely: 1.Psilopsida 2.Lycopsida 3.Sphenopsida 4.Pteropsida
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Pteridophytes Life Cycle
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any vascular plant that reproduces by means of an exposed seed, or ovule. The seeds of many gymnosperms (literally “naked seeds”) are borne in cones and are not visible until maturity. Gymnosperm Conifers Cycads Ginko
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Gymnosperms Gymnosperms are seed-bearing vascular plants, such as cycads, ginkgo, yews and conifers, in which the ovules or seeds are not enclosed in an ovary. The word "gymnosperm" comes from the Greek word gymnospermos, meaning "naked seeds". Gymnosperm seeds develop either on the surface of scale or leaf-like appendages of cones, or at the end of short stalks. The largest group of living gymnosperms are the conifers (pines, cypresses and relatives) and the smallest is ginkgo, a single living plant species found in China. There are around 1000 species of gymnosperm.
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Gymnosperm Life Cycle
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Angiosperms are plants that produce flowers and bear their seeds in fruits. They are the largest and most diverse group within the kingdom Plantae, with about 300,000 species.... Angiosperms also comprise the vast majority of all plant foods we eat, including grains, beans, fruits, vegetables, and most nuts. Angiosperms
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Angiosperms are seed-bearing vascular plants. Their reproductive structures are flowers in which the ovules are enclosed in an ovary. Angiosperms are found in almost every habitat from forests and grasslands to sea margins and deserts. Angiosperms display a huge variety of life forms including trees, herbs, submerged aquatics, bulbs and epiphytes. The largest plant families are Orchids, and Compositae (daisies) and Legumes (beans). There are an estimated 352,000 species of flowering plants or angiosperms.
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Dicot vs Monocot
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Summary of the monocot phylogenetic tree, indicating families
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