Full-text resources of PSJD and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl

Refine search results

Journals help

  1. 2 Kosmos

Years help

  1. 2 2002

Authors help

  1. 2 Kuta E.

  2. 2 Rojek J.

Preferences help
Polish version English version Language
enabled [disable] Abstract
Number of results

Results found: 2

Number of results on page
first rewind previous Page / 1 next fast forward last

Search results

help Sort By:

help Limit search:
first rewind previous Page / 1 next fast forward last
1
Content available remote

Bielmo - tkanka odżywiająca zarodek I. Bielmo u roślin okrytonasiennych (Angiospermae) jako wynik podwójnego zapłodnienia

100%
Rojek J., Kuta E.
Kosmos
|
2002
|
vol. 51
|
issue 1
69-83
EN
Summary A review is given on advances in endosperm research in angiosperms. Endosperm is a very important nutritive tissue for the developing embryo. In sexually reproducing angiosperms endosperm develops as a consequence of double fertilization when one of male gametes is introduced to the central cell of megagametophyte. Of the three types of endosperm: nuclear, cellular and helobial, the nuclear pattern of development is most common and occurs in plants of major economic importance, including the cereals. Recently research is focused on processes and mechanisms involved in endosperm development in species with the nuclear type of endosperm, including monocots (mainly cereals) and dicots (the model plant Arabidopsis thaliana). This model represents a highly conserved mode of nuclear endosperm differentiation with several stages: coenocytic, cellularization, differentiation, maturation and programmed death. In the differentiated endosperm four major cell types have been recognized: starchy endosperm, aleurone cells, transfer cells, and the cells of the embryo-surrounding region. The mechanisms involved in the first two stages of endosperm development are very conserved among all groups of angiosperms; they involve nuclear migration during coenocytic stage and cell wall formation by cytoplasmic phragmoplasts. Also specification of cell fates via positional signaling and genetic basis of endosperm differentiation are reported. Several other topics are presented, such as endosperm cytology, the nature and origin of endosperm dosage system, mutation fie in Arabidopsis that allows endosperm development without fertilization, and endosperm development in vitro after the fusion of an isolated sperm and isolated central cell.
2
Content available remote

Bielmo - tkanka odżywiająca zarodek II. Autonomiczny rozwój bielma u roślin okrytonasiennych (Angiospermae)

100%
Kuta E., Rojek J.
Kosmos
|
2002
|
vol. 51
|
issue 1
85-97
EN
Summary In sexually reproducing flowering plants both embryo and endosperm development is initated by fertilization (double fertilization) and in the vast majority of these plants a ratio of 2 maternally derived genomes to 1 paternally derived genom (2m:1p) is essential for endosperm formation and therefore for seed development. However, there is a group of taxa in which reproductive development is fertilization-independent. The occurrence of autonomous endosperm is well-known phenomenom in autonomous apomicts and a very rare one in amphimictic taxa. The development of fertilization-independent endosperm can be induced experimentally with the use of irradiated pollen and also through in vitro culture of unfertilized ovules or ovaries. In this review the problem of genomic imprinting is discussed in the light of autonomous endosperm development without paternal genome involvement. How genomic imprinting can be overcome in the case of autonomous endosperm development in flowering plants?
first rewind previous Page / 1 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.