The Plant Kingdom The systems of classification of the mark kingdom deviate in naming and placing the larger categories (even the divisions) because in that respect is little legitimate fogey evidence, as there is in the case of animals, to name the unbent evolutionary relationships of and distances between these groups. However, comparisons of nucleic acid sequences in dresss atomic number 18 without delay serving to clarify such relationships among plants as well as other organisms. A widely held view of plant evolution is that the ancestors of area plants were primitive algae that made their panache from the ocean to freshwater system, where they inhabit alternately wet-and-dry shoreline environments, eventually giving approach to such posterior forms as the mosses and ferns. From some remote fern ancestor, in turn, arose the seed plants. The plant kingdom traditionally was divided into fanatic large groups, or subkingdoms, based chiefly on generative mental sy nthesis. These are the thallophytes (subkingdom Thallobionta), which do not form embryos, and the embryophytes (subkingdom Embryobionta), which do. All embryophytes and near thallophytes have a life cycle in which there are two alternating generations (see reproduction). The plant form of the thallophytes is an unvarying thallus omiting authoritative(a) roots, stems, and leaves. The subkingdom Thallobionta is sedate of more than 10 divisions of algae and fungi (once considered plants).

The subkingdom Embryobionta is composed of two groups: the bryophytes (liverwort and moss), division Bryophyta, which have no v ascular tissues, and a group consisting of s! even divisions of plants that do have vascular tissues. The Bryophyta, wee-wee care other nonvascular plants, are simple in structure and lack true roots, stems, and leaves; they therefore usually live in moist places or in water. The vascular plants have true roots, stems, and leaves and a well-developed vascular system composed of xylem and phloem for transporting water and nourishment throughout the... If you want to get a all-inclusive essay, rules of order it on our website:
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