Results 211 to 220 of about 21,195 (259)

Lignified sieve elements in the wheat leaf

Planta, 1974
Sieve elements with thick, lignified walls are identified in the longitudinal bundles of the wheat leaf and appear to be functional. They are also present in several festucoid grasses but appear to be absent from the panicoid grasses examined.
J, Kuo, T P, O'Brien
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Removing the nucleus in sieve elements

Science, 2014
Cellular remodeling to develop phloem cells orchestrates degradation of the cell’s nucleus.
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Sieve Elements of Graft Unions

1990
In grafted plants the various relations between scion and stock are based on exchange of heterogeneous substances between the partners; many of them being organic compounds which are translocated in the symplast (see reviews by Brabec 1965 and Carr 1976).
Rainer Kollmann, Christl Glockmann
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Endoplasmic reticulum in the sieve element of Cucurbita

Journal of Ultrastructure Research, 1968
The endoplasmic reticulum (ER) in immature sieve elements of Cucurbita maxima Duchesne resembles that of other types of nucleate cells in morphology and distribution. In mature sieve elements the ER assumes two forms. One of these is represented by a network closely applied to the plasma membrane lining the cell wall.
K, Esau, J, Cronshaw
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Sieve element plastids in bamboo

Experientia, 1978
The fine structure of the sieve element plastids ofBambusa vulgaris andSchizostachyum lumampao revealed the typical monocotyledonous type (P-type) with the cuneate proteinaceous bodies and lattice-like crystalloids; in addition, characteristically formed vesicles and tubulae could be observed. The diagnostic value of these plastids is also discussed.
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A reevaluation of extruded nucleoli in sieve elements

Journal of Ultrastructure Research, 1970
Immature and mature sieve elements of Populus deltoides, Quercus alba, Salix nigra, Tilia americana, and Rhus glabra were examined with light and electron microscopes. Sieve elements of the first four species contain persistent spherical inclusions similar to those heretofore interpreted as extruded nucleoli.
B P, Deshpande, R F, Evert
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Wound-Sieve Elements

1990
The survival of higher plants is highly dependent upon the phloem path linking assimilate sources and sinks. In an individual plant the elongation, capacity and function of this path have to be finely adjusted to internal and environmental conditions.
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Sieve-Element Structure

1975
Although it is now more than a hundred years since Hartig (1837, 1860) first discovered sieve tubes, and associated solute transport with sieve elements, the structure of functioning sieve elements and the mechanism of phloem transport are still controversial issues.
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Microtubules in differentiating sieve elements of Gossypium hirsutum

Journal of Ultrastructure Research, 1982
Changes in distribution, orientation, and abundance of microtubules (MT) in relation to sieve element differentiation in root protophloem and stem and midvein metaphloem of Gossypium hirsutum were studied at the ultrastructural level. Depending on their stage of differentiation the sieve elements were divided into four previously characterized groups ...
J, Thorsch, K, Esau
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Sieve Element Cell Walls

1975
Sieve elements typically have non-lignified cellulosic walls similar to those of parenchyma cells. The walls are often thickened and in most instances this thickening is described as “nacreous” thickening or the “nacre” wall. The term “nacre” was introduced because of the refractve properties of this wall and its characteristic lustre when viewed with ...
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