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Non-vascular plants are plants without a vascular system consisting of xylem and phloem. Instead, they may possess simpler tissues that have specialized functions for the internal transport of water. Instead, they may possess simpler tissues that have specialized functions for the internal transport of water.
Plants with microphyll leaves occur early in the fossil record, and few such plants exist today. In the classical concept of a microphyll, the leaf vein emerges from the protostele without leaving a leaf gap. Leaf gaps are small areas above the node of some leaves where there is no vascular tissue, as it has all been diverted to the leaf.
The bryophytes and vascular plants (embryophytes) also have embryonic development which is not seen in green algae. [45] While bryophytes have no truly vascularized tissue, they do have organs that are specialized for transport of water and other specific functions, analogous for example to the functions of leaves and stems in vascular land plants.
Chloroplasts (green discs) and accumulated starch granules in cells of Bryum capillare. Botanically, mosses are non-vascular plants in the land plant division Bryophyta. They are usually small (a few centimeters tall) herbaceous (non-woody) plants that absorb water and nutrients mainly through their leaves and harvest carbon dioxide and sunlight to create food by photosynthesis.
Botanists define vascular plants by three primary characteristics: Vascular plants have vascular tissues which distribute resources through the plant. Two kinds of vascular tissue occur in plants: xylem and phloem. Phloem and xylem are closely associated with one another and are typically located immediately adjacent to each other in the plant.
Early Devonian plants did not have roots or leaves like the plants most common today, and many had no vascular tissue at all. They probably relied on arbuscular mycorrhizal symbioses with fungi to provide them with water and mineral nutrients such as phosphorus.
Pteridophytes (ferns and lycophytes) are free-sporing vascular plants that have a life cycle with alternating, free-living gametophyte and sporophyte phases that are independent at maturity. The body of the sporophyte is well differentiated into roots, stem and leaves. The root system is always adventitious. The stem is either underground or ...
In most seed plants, especially woody types, the endodermis is present in roots but not in stems. The endodermis helps regulate the movement of water, ions and hormones into and out of the vascular system. It may also store starch, be involved in perception of gravity and protect the plant against toxins moving into the vascular system.