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Cavitation is when the plant cannot supply its xylem with adequate water so instead of being filled with water the xylem begins to be filled with water vapor. These particles of water vapor come together and form blockages within the xylem of the plant. This prevents the plant from being able to transport water throughout its vascular system. [16]
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 pistil or directly through ovule tissue in some gymnosperms.
The transport of water along this pathway occurs in components, variously defined among scientific disciplines: Soil physics characterizes water in soil in terms of tension, Physiology of plants and animals characterizes water in organisms in terms of diffusion pressure deficit, and
Epilobium hirsutum seed head dispersing seeds. In spermatophyte plants, seed dispersal is the movement, spread or transport of seeds away from the parent plant. [1] Plants have limited mobility and rely upon a variety of dispersal vectors to transport their seeds, including both abiotic vectors, such as the wind, and living vectors such as birds.
Hydraulic redistribution is a passive mechanism where water is transported from moist to dry soils via subterranean networks. [1] It occurs in vascular plants that commonly have roots in both wet and dry soils, especially plants with both taproots that grow vertically down to the water table, and lateral roots that sit close to the surface.
Also, plants with deep reaching roots can transpire water more constantly, because those roots can pull more water into the plant and leaves. Another example is that conifer forests tend to have higher rates of evapotranspiration than deciduous broadleaf forests, particularly in the dormant winter and early spring seasons, because they are ...
Although several mechanisms have been proposed to explain how sap moves through the xylem, the cohesion-tension mechanism [1] has the most support. Although cohesion-tension has received criticism due to the apparent existence of large negative pressures in some living plants, experimental and observational data favor this mechanism.
Polar auxin transport is the regulated transport of the plant hormone auxin in plants. It is an active process, the hormone is transported in cell-to-cell manner and one of the main features of the transport is its asymmetry and directionality . The polar auxin transport functions to coordinate plant development; the following spatial auxin ...