Results 191 to 200 of about 5,391 (216)
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American Journal of Botany, 1949
probably more than elsewhere in the hierarchy of taxonomic categories, nomenclature and phylogeny come in close contact and are frequently in conflict. This instability in the application of nomenclaturally safe designations for many higher categories is hardly more desirable than it is with regard to the lower categories. New systems of classification
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probably more than elsewhere in the hierarchy of taxonomic categories, nomenclature and phylogeny come in close contact and are frequently in conflict. This instability in the application of nomenclaturally safe designations for many higher categories is hardly more desirable than it is with regard to the lower categories. New systems of classification
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Auxin Balance in the Avena Coleoptile
Physiologia Plantarum, 1974AbstractColeoptiles of Avena possessed the capacity to degrade infiltrated indole‐3‐acetic acid (IAA). This activity decreased along the length of the coleoptile from apex to base on the bases of fresh weight, dry weight and protein; the apical 1 cm segment degraded more IAA than segments from other parts of the coleoptile.
Poul Larsen, R. Rajagopal
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Kinetic modelling of phototropism in maize coleoptiles [PDF]
Planta, 1987 Blue-light-induced phototropism of maize (Zea mays L.) coleoptiles was studied with a view to kinetic models. Red-light-grown plants were used to eliminate complication arising from the activation by blue light of phytochrome-mediated phototropism. In the first part, mathematical models were developed to explain the phototropic fluence-response data ...
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Intra- and extracytoplasmic microtubules in coleoptiles of Avena
Journal of Ultrastructure Research, 1972A study is made of microtubules in normal young elongating cells of coleoptiles of Avena . In the cytoplasm are found large masses consisting entirely of microtubules. There are many strong indications that the microtubules can pass directly through the cell membranes. Extracytoplasmic microtubules are universally present in the outer, hyaline layer
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American Journal of Botany, 1965
The vascular bundles in the uppermost 1‐4 mm of the coleoptiles of 9 varieties of Avena sativa, and also of Avena fatua L., all terminate essentially vertically with a small “cap” of tracheary elements. In Triticum vulgare Vill., by contrast, they terminate with a horizontal or downward‐pointing section.
Kenneth V. Thimann, Terence P. O'Brien
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The vascular bundles in the uppermost 1‐4 mm of the coleoptiles of 9 varieties of Avena sativa, and also of Avena fatua L., all terminate essentially vertically with a small “cap” of tracheary elements. In Triticum vulgare Vill., by contrast, they terminate with a horizontal or downward‐pointing section.
Kenneth V. Thimann, Terence P. O'Brien
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A cytological study of the oat coleoptile
Australian Journal of Botany, 1964A study has been made of the cytoplasmic organization of epidermal and sub- epidermal parenchyma of oat coleoptiles both before and after the onset of extension growth. In the youngest cells studied (coleoptiles 0.5 mm long) the epidermal parenchyma was characterized by large stellate vacuoles and by the secretion of vesicles through the plasmalemma ...
RC Foster, AB Wardrop
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RELATIONS OF RESPIRATION AND GROWTH IN THE AVENA COLEOPTILE
American Journal of Botany, 1949THE AVENA coleoptile is a classical obj ect for the study of the effect of auxin in inducing plant growth. A particularly simple system for the study of the auxin response is constituted by excised sections of the coleoptile which when floated on aqueous solutions containing an active auxin, are capable of extensive and rapid growth (Bonner, 1933).
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Phototropism of stems, roots and coleoptiles
1959Cylindrical plant organs placed in a gradient of visible light energy generally react by growing toward or away from the brighter light (Fig. 1). Such bending or curvature, due to unequal growth rates on the two sides of the differentially illuminated organ, is referred to as phototropism. While the basic phenomenon must have been familiar to botanists
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Stimulation of rice coleoptile growth by ethylene
Planta, 1970The growth rate of rice coleoptiles is increased by low concentrations of ethylene, especially in oxygen concentrations lower than air; carbon dioxide enhanced this response. C2H4 is produced by rice seedlings, and this production is also enhanced by carbon dioxide.
Hiroshi Suge +3 more
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Ascorbic Acid in the Avena Coleoptile
Botanical Gazette, 19371. Ascorbic acid is present in considerable concentrations in Avena coleoptiles from etiolated seedlings. 2. On the basis of wet weight determinations, reduced ascorbic acid is present in higher concentrations in tips than in bases of coleoptiles, and oxidized ascorbic acid shows the reverse gradient of distribution. 3.
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