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Chloroplasts in leaf cells of the moss Mnium stellare. Plant anatomy or phytotomy is the general term for the study of the internal structure of plants.Originally, it included plant morphology, the description of the physical form and external structure of plants, but since the mid-20th century, plant anatomy has been considered a separate field referring only to internal plant structure.
Runcaria has all of the qualities of seed plants except for a solid seed coat and a system to guide the pollen to the seed. [3] Runcaria was followed shortly after by plants with a more condensed cupule, such as Spermasporites and Moresnetia. Seed-bearing plants had diversified substantially by the Famennian, the last stage
All spermatophytes ("seed plants") possess flowers as defined here (in a broad sense), but the internal organization of the flower is very different in the two main groups of spermatophytes: living gymnosperms and angiosperms. Gymnosperms may possess flowers that are gathered in strobili, or the flower itself may be a strobilus of fertile leaves.
Calamopityaceae is the largest family of the division of extinct seed-bearing plants (spermatophytes) known as Pteridospermatophyta. [1] [2] It is the only family in the monotypic order Calamopityales. [3] This family is characterized by its petioles and specific wood pattern, and it grew only in the Paleozoic era, specifically in North America ...
Seed bearing organs of Pentoxylales, dubbed Carnoconites, which have a central axis or peduncle, which branches into numerous structures that end with an ovule. The morphology has variously been described as infructescences, seed cones, seed-bearing fruits, or female flowers. The seeds are apparently sessile. [1]
In seed plants, the embryo will develop one or more "seed leaves" . By the end of embryogenesis, the young plant will have all the parts necessary to begin in its life. Once the embryo germinates from its seed or parent plant, it begins to produce additional organs (leaves, stems, and roots) through the process of organogenesis.
Leguminous seeds are examples of such sclerification. Larger sclereids form columns in the epidermis of pea, bean, and soybean seeds, and bone-shaped osteosclereids occur beneath the epidermis. In the seed coats of coconuts, sclereids possess numerous bordered pits. [2] These larger macrosclereids found in seed coats are of protodermal origin. [4]
The formation of the seed is the defining part of the process of reproduction in seed plants (spermatophytes). Other plants such as ferns, mosses and liverworts, do not have seeds and use water-dependent means to propagate themselves. Seed plants now dominate biological niches on land, from forests to grasslands both in hot and cold climates.