(1) The dynamics of growth processes was studied in the integument and nucellus of Pinus silvestris during the year of fertilization.
(2) The growth of micropylar part of the nucellus and integument proceeds, mainly at the expense of cell proliferation.
(3) Pollination stimulated accumulation of several reserve substances and enzymes in the tip of nucellus beak, micropylar zone and these included starch, peroxidase, phosphorylase succinate dehydrogenase, cytochrome oxidase etc.
(4) Nucellus cells also stored diverse substances and enzymes especially towards the chalazal end.
(5) Recovery from the repressor did not occur readily in Citrus nucellus following recultures in citron-ovule-free medium; carrot callus resumed normal embryogenesis immediately upon transfer to suppressor-free medium.
(6) The larges nuclei are situated in the micropylar part of nucellus.
(7) Citrus reticulata Blanco Ponkan mandarin nucellus explants and Daucus carota L. 'Queen Anne's Lace' callus were employed to examine effects of known plant growth regulators and to determine possible identity of one or more of them with the repressive factor.
(8) In the part of nucellus concrescent with the integument, the mitotic activity disappears still prior to fertilization and the growth proceeds, mainly, at the expense of cell elongation.
(9) It could arise from a damage of the feeding function of the nucellus.
(10) The nucellus of Zea mays contains many enzymes required for hydrolysis of reserved food substances.
(11) The growth of two parts of the nucellus and integument under study is described by an S-shaped curve but the dynamics of growth processes and the ratio of cell reproduction and elongation differ in each tissue.
(12) In ovaries sampled before and after fertilization, a 3H-labeled histone RNA probe was localized in the cells of the pericarp, outer integument and nucellus but binding of the probe decreased as these tissues senesced.
(13) Pollination stimulated the accumulation of several substances and enzymes in the tip of the nucellus, micropylar zone.
Sporangium
Definition:
(n.) A spore case in the cryptogamous plants, as in ferns, etc.
Example Sentences:
(1) This "belt," usually first observed toward the center of the sporangium, developed without changing thickness or appearance over the surface of the forespore.
(2) It is proposed that simple, eucarpic, monocentric chytrids which discharge zoospores following dissolution of the sporangium wall evolved into multipapilliate species of Rhizophydium and 2 lines of evolution from these species are documented with examples.
(3) The cytoplasmic sporangium cleavage is brought about by the fusion of flagellar sheaths and cleavage vesicles.
(4) The mature resting sporangium (RS) wall of Coelomomyces dodgei (Chytridiomycetes; Blastocladiales) consists of three principal layers: (I) an outer pigmented layer (1.8-2.2 microns) that contains polysaccharide, (II) a middle electron translucent layer (1.3-1.6 microns) comparatively free of polysaccharide, and (III) an inner layer (125 nm) rich in polysaccharide that surrounds the meiospores.
(5) By inference, the sporulation division septum locus is distal to the ultimate normal cell division septum, i.e., proximal to the "old" pole of the B. megaterium sporangium.
(6) With the progress of spore encapsulation, the tyrocidine production migrated from the soluble fraction into the forespore, terminating with the separation of forespores from the sporangium membrane.
(7) Similarity of these bodies to sporangium-like structures is suggested.
(8) Using a transcriptional fusion of the spoIVC gene to the lacZ gene of Escherichia coli, we found that spoIVC expression was turned on at the third to fourth hour of sporulation (at about the developmental stage [IV] that its products are required in spore formation) and that this transcription was largely restricted to the mother cell chamber of the sporangium.
(9) However, a decrease in bacterial toxicity occurred with sporangium lysis.
(10) The transcriptional activity of the two genomes of the sporangium during spore formation was determined by pulse-labeling bacteria with 3H-uracil at different times of sporulation and preparing them for high resolution autoradiography.
(11) It was placed into group 3 of the genus Bacillus on the basis of its cellular morphology, the morphology of the sporangium, and the location of the spore within the cell.
(12) This suggests that the selective incorporation into the sporangium of either the "older" or "younger" chromosome of a vegetative cell does not occur in the course of spore formation.
(13) To investigate whether expression of spoIIM is required in the forespore compartment of the sporangium, we have constructed a new integrational vector, pKSV7, which contains temperature-sensitive replication functions derived from pE194ts.
(14) The electronmicroscopic examination of the colony revealed sporangium containing spores and characteristic dense body and plastids in the spores.
(15) The ability of Achlya to incorporate [1-14C]acetate into lipid was maximal at the time of sporangium formation, and glycerides were the principal component of total lipid to become 14C-labelled at all stages of the life cycle.
(16) The transcellular electric current apparently plays no role in sporangium formation or in spore cleavage.
(17) The peritumoural region of a squamous cell carcinoma of the tongue when examined with light and electron microscope showed nodular bodies in the submucosa with all the distinctive features of 'sporangium and 'spores' of rhinosporidiosis.
(18) A septum within each sporangium divides the forespore from the basal or parasporal portion of the cell.
(19) Sporulation in Bacillus subtilis is a simple developmental system in which a single cell undergoes differentiation to two 'sister' cells, namely the prespore and the sporangium.
(20) Subsequently, the young cell elongates, becomes somewhat deformed, and then emerges through a narrow aperture in the inflexible coats of the spore, finally rupturing the sporangium.