Wyniki wyszukiwania

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Calcium ion presence as a trait of receptivity in tenuinucellar ovules of Galanthus nivalis L.

100%

Chudzik B., Sniezko R.

Acta Biologica Cracoviensia. Series Botanica

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2003

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tom 45

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nr 1

In Galanthus nivalis during the progamic phase, both the embryo sac and somatic cells of the ovule change their ultrastructure and physiology, as observed by light, fluorescence, and electron microscopy. Fresh ovules from buds, opening flowers, and from cross-pollinated flowers were stained in toto to detect pectins, acidic polysaccharides, proteins, lipids, callose, free calcium ions and membrane-bound calcium. These substances were found only in the micropylar part of fertile ovules. All stainings were negative in sterile ovules. In EM, the somatic cells in the micropylar part of the ovule were observed to develop secretion activity. Their exudates passed to the intercellular spaces, mainly to the micropylar canal. The amount of the exudate increased after pollination. Free or loosely bound calcium ions were present in extracellular regions of the micropylar part of fertile ovules. The substances detected in the micropylar exudate of fertile ovules are suggested to support and direct pollen tube growth to the embryo sac.

2

Structure and ultrastructure of the egg capsule of Thermobia domestica [Packard] [Insecta, Zygentoma]

100%

Poprawa I., Rost M. M.

Folia Biologica

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2004

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tom 52

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nr 3-4

3

Apoplastic system of the gynoecium and embryo sac in relation to function

80%

Yang H. Y.

Acta Biologica Cracoviensia. Series Botanica

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2001

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tom 43

This article addresses the gynoecium and embryo sac from a fresh viewpoint, that is, in terms of the apoplastic system involved in the pistil and its putative functions in sexual processes. This system includes the extracellular matrix of the pollen tube track and particularly the micropyle and synergids, the intercellular space between the cells of the female germ unit, and the apoplast surrounding the embryo sac. Most of the data cited are research results established during the last decade, mainly from ultrastructural and cytochemical observations, which give interesting and important information about the apoplastic system concerned.

Ograniczanie wyników

2 Acta Biologica Cracoviensia. Series Botanica

1 Folia Biologica

1 Chudzik B.

1 Poprawa I.

1 Rost M. M.

1 Sniezko R.

1 Yang H. Y.

1 2004

1 2003

1 2001

Calcium ion presence as a trait of receptivity in tenuinucellar ovules of Galanthus nivalis L.

Structure and ultrastructure of the egg capsule of Thermobia domestica [Packard] [Insecta, Zygentoma]

Apoplastic system of the gynoecium and embryo sac in relation to function