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Historically, vascular plants were known as "higher plants", as it was believed that they were further evolved than other plants due to being more complex organisms. However, this is an antiquated remnant of the obsolete scala naturae , and the term is generally considered to be unscientific.
Among living plants, this type of stele is found only in the stems of ferns. Most seed plant stems possess a vascular arrangement which has been interpreted as a derived siphonostele, and is called a eustele – in this arrangement, the primary vascular tissue consists of vascular bundles, usually in one or two rings around the pith. [12]
Plant morphology treats both the vegetative structures of plants, as well as the reproductive structures. The vegetative (somatic) structures of vascular plants include two major organ systems: (1) a shoot system, composed of stems and leaves, and (2) a root system. These two systems are common to nearly all vascular plants, and provide a ...
A plant derived from the asexual vegetative reproduction of a parent plant, with both plants having identical genetic compositions. coalescent Having plant parts fused or grown together to form a single unit. cochleariform Concave and spoon-shaped. cochleate Coiled like a snail's shell. coenobium An arranged colony of algae that acts like a ...
Because the plant vascular system is vital in growth and development of plant cells and the organs within the plant, the role of sieve elements in the transport of necessary carbohydrates and macromolecules is largely expanded. This can be applied to agriculture to observe the way resources are distributed to various parts of the plant.
In heterosporous seedless vascular plants, modified leaves called microsporophylls bear microsporangia containing many microsporocytes that undergo meiosis, each producing four microspores. Each microspore may develop into a male gametophyte consisting of a somewhat spherical antheridium within the microspore wall.
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.
Vascular tissue is a complex conducting tissue, formed of more than one cell type, found in vascular plants. The primary components of vascular tissue are the xylem and phloem. These two tissues transport fluid and nutrients internally. There are also two meristems associated with vascular tissue: the vascular cambium and the cork cambium. All ...