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Some plants also form smaller tubers or tubercules that act like seeds, producing small plants that resemble (in morphology and size) seedlings. Some stem tubers are long-lived, such as those of tuberous begonias , but many plants have tubers that survive only until the plants have fully leafed out, at which point the tuber is reduced to a ...
A pollen tube is a tubular structure produced by the male gametophyte of seed plants when it germinates. Pollen tube elongation is an integral stage in the plant life cycle. The pollen tube acts as a conduit to transport the male gamete cells from the pollen grain—either from the stigma (in flowering plants) to the ovules at the base of the ...
In plant anatomy, there are two main types of sieve elements. Companion cells and sieve cells originate from meristems, which are tissues that actively divide throughout a plant's lifetime. They are similar to the development of xylem, a water conducting tissue in plants whose main function is also transportation in the plant vascular system. [1]
1. In flowering plants, a ring of structures that may be united in a tube, arising from the corolla or perianth of a flower and standing between the perianth lobes and the stamen s. The trumpet of a daffodil is a corona. 2. In grasses, a hardened ring of tissue surmounting the lemma in some species. cortex. pl. cortexes or cortices
In angiosperms, a hypanthium or floral cup [1] [2] [3] is a structure where basal portions of the calyx, the corolla, and the stamens form a cup-shaped tube. It is sometimes called a floral tube, a term that is also used for corolla tube and calyx tube. [citation needed] It often contains the nectaries of the plant.
The tunics of some species are thin, dry, and papery, at least in young plants, however, in some families, such as Iridaceae, the tunic of a mature corm can be formidable protection. For example, some of the larger species of Watsonia accumulate thick, rot-resistant tunics over a period of years, producing a structure of tough, reticulated fibre.
By 1963, a new structural system of framed tubes had appeared in skyscraper design and construction. Fazlur Rahman Khan, a structural engineer from Bangladesh (then called East Pakistan) who worked at Skidmore, Owings & Merrill, defined the framed tube structure as "a three dimensional space structure composed of three, four, or possibly more frames, braced frames, or shear walls, joined at or ...
A geophyte (earth+plant) is a plant with an underground storage organ including true bulbs, corms, tubers, tuberous roots, enlarged hypocotyls, and rhizomes. Most plants with underground stems are geophytes but not all plants that are geophytes have underground stems. Geophytes are often physiologically active even when they lack leaves.