The capsule development of Tetraplodon angustatus and T. mnioides was studied by placing emphasis on spore releasing mechanism. The same developmental pattern is observed in both species. Inside the capsule with multi-layered archesporium, a false columella (the axial tissue cylinder below the true columella) begins to develop. This structure consists of small cells. When the capsule matures and opens, the true columella degenerates while the false columella develops further by cell elongation. Spores are pushed out from urn subsequently. A lysigenous cavity often develops in the middle of apophysis, containing probably aromatic substances. The one to two-layered annulus consisting of two to three rows of small cells with irregularly thickened walls is a specialized mechanism for operculum removal. РезюмеРазвитие коробочек Tetraplodon angustatus и Т mnioides изучали, обращая особое вни мание на механизм высвобождения спор. Коробочка у обоих видов развивается сходным образом. В коробочке, имеющей многослойный археспорий, начинает формироваться структура, названная здесь ложной колонкой. Ложная колонка, цилиндр осевой ткани, расположена под настоящей колонкой и до вскрывания коробочки состоит из очень мелких клеток. К моменту вскрывания коробочки, после отмирания настоящей колонки, ложная колонка начинает расти благодаря растяжению клеток, в результате чего споры постепенно выталкиваются из урночки. В центре апофизы ко времени вскрывания коробочки часто развивается лизигенная полость, содержащая, вероятно, пахучие вещества Одно-двухслойное двух-трехрядное колечко, состоящее из мелких клеток с неравномерно утолщенными стенками, является специализированным механизмом для удаления крышечки. attractant for flies, such as odor produced by
The study analyses daily activities of youth in the virtual and actual environment within the framework of theoretical and applied achievements of time geography. The role of mobile devices in youth life, transformation of traditional activity and changes in the daily organization of actions due to digitalization are discussed. Empirical data for the research were obtained via a diary method (the respondents were 18–22-year-old students). Features of individual daily foreground and background activities, digital devices used, activities relation and localization are evaluated by geovisualization performed within the time-geographical concepts. Regardless of the smartphonization, individuals reserve time spans not associated with virtual activities; their online activities are localized within places of residence, study and traffic routes, while public spaces serve as “live communication” platforms (but a complete rejection of virtual activity does not occur here). An attempt to compare youth daily activity under ordinary conditions and during the period of forced isolation during the COVID-19 pandemic is being made.
The annulus of Tetraplodon angustatus B. S. G. has been studied with transmission electron microscopy and of Tayloria tenuis (With.) Schimp. with scanning electron microscopy. Both species have an annulus which serves as a dehiscence mechanism of the capsule. Dehiscence takes place through cell wall separation at the middle lamella. The annulus remains attached to the operculum. Longitudinal section of the capsule of T. angustatus shows an annulus consisting of three cells in two layers (outer with two cells, inner with one cell). Ultrastructural peculiarities of the annulus cells are: 1) alternating electron-dense and more electron-translucent areas in the cell walls, representing a system of radial canals in the cell wall; 2) dense cytoplasm lacking vacuoles and occupying only a part of cell volume; 3) extraplasmic space and cell wall canals filled with a substance that appears to be mucilage; 4) outer parts of outer cell walls especially electron-dense and stratified. The annulus cells are considered to produce mucilage and hydrolytic enzymes in the course of their development. ÐåçþìåÑòðîåíèå êîëå÷êà èçó÷àëè ó äâóõ âèäîâ ñïëàõíîâûõ -Tayloria tenuis (ñ ïîìîùüþ ñêàíèðóþùåé ýëåêòðîííîé ìèêðîñêîïèè) è Tetraplodon angustatus (ñ ïîìîùüþ òðàíñìèññèîííîé ýëåêòðîííîé ìèêðîñêîïèè). Âñêðûâàíèå êîðîáî÷êè ïðîèñõîäèò ïóòåì ðàñõîaeäåíèÿ ñìåaeíûõ îáîëî÷åê êëåòîê êîëå÷êà è êðàÿ óðíî÷êè â îáëàñòè ñðåäèííîé ïëàñòèíêè. Êîëå÷êî îñòàåòñÿ íà êðûøå÷êå. Íà ïðîäîëüíîì ðàçðåçå êîðîáî÷êè T. angustatus êîëå÷êî ñîñòîèò èç òðåõ êëåòîê (â íàðóaeíîì ñëîå äâå êëåòêè, âî âíóòðåííåì -îäíà). Óëüòðàñòðóêòóðíûìè îñîáåííîñòÿìè êëåòîê êîëå÷êà ÿâëÿþòñÿ: 1) ÷åðåäîâàíèå â èõ îáîëî÷êàõ ýëåêòðîííî-ïëîòíûõ ó÷àñòêîâ ñ áîëåå ýëåêòðîííî-ïðîçðà÷íûìè, îáðàçóþùèìè ñèñòåìó ðàäèàëüíûõ êàíàëüöåâ îáîëî÷êè; 2) ãóñòàÿ öèòîïëàçìà áåç âàêóîëåé, çàíèìàþùàÿ ëèøü ÷àñòü îáúåìà êëåòêè; 3) çàïîëíåííîñòü ýêñòðàïëàçìàòè÷åñêîãî ïðîñòðàíñòâà è êàíàëüöåâ îáîëî÷êè ñëèçüþ; 4) îáðàçóþùèå ïîâåðõíîñòü êîðîáî÷êè ó÷àñòêè ñòåíîê êëåòîê êîëå÷êà èìåþò îñîáî âûñîêóþ ýëåêòðîííóþ ïëîòíîñòü è ñëîèñòóþ ñòðóêòóðó. Âåðîÿòíî, â õîäå ñâîåãî ðàçâèòèÿ êëåòêè êîëå÷êà ïðîèçâîäÿò ñëèçü, íàêàïëèâàþùóþñÿ â ýêñòðàïëàçìàòè÷åñêîì ïðîñòðàíñòâå, è ãèäðîëèòè÷åñêèå ôåðìåíòû, âûçûâàþùèå â êîíöå ðàçâèòèÿ êëåòîê èçáèðàòåëüíûé ãèäðîëèç èõ îáîëî÷åê. Ñëèçü àáñîðáèðóåò âîäó èç öèòîïëàçìû êëåòîê êîëå÷êà, à òàêaeå è èç ñîñåäíèõ êëåòîê, ÷òî ïðèâîäèò ê îäíîâðåìåííîìó óâåëè÷åíèþ îáúåìà êëåòîê êîëå÷êà è óìåíüøåíèþ îáúåìà ñîñåäíèõ êëåòîê è, êàê ñëåäñòâèå, ê âñêðûâàíèþ êîðîáî÷êè. INTRODUCTIONMost mosses of subclass Bryidae are stegocarpous (operculate), i.e. their capsules are opened by removal of an operculum. The operculum separates from the urn by means of an annulus, formed of one to several concentric rows of hygroscopic exothecial cells at the operculum-urn boundary.The structure of annulus is very variable in
ÐåçþìåÁëåôàðîïëàñò Tayloria tenuis èìååò â öåëîì òèïè÷íîå äëÿ ëèñòîñòåáåëüíûõ ìõîâ ñòðîåíèå, íî, â îòëè÷èå îò áîëüøèíñòâà èçó÷åííûõ ðàíåå âèäîâ, îáëàäàåò òàêîé îðèåíòàöèåé áàçàëüíûõ òåëåö ïî îòíîøåíèþ ê ïðîäîëüíîé îñè ñëîÿ S 1 , êîãäà ïåðåäíåå áàçàëüíîå òåëüöå îòêëîíÿåòñÿ îò íåå âïðàâî, à çàäíåå áàçàëüíîå òåëüöå åé ïàðàëëåëüíî. Ñëîé S 1 â ñàìîì øèðîêîì ó÷àñòêå ñîñòîèò èç 13 ìèêðîòðóáî÷åê, àïåðòóðà çàêðûòàÿ, äîñòèãàþùàÿ øèðèíû â 2 äèàìåòðà ìèêðîòðóáî÷êè. Èç ñðàâíåíèÿ ñòðîåíèÿ áëåôàðîïëàñòà T. tenuis è èçó÷åííîãî ðàíåå âèäà Funaria hygrometrica (Carothers, Brown, 1985) âèäíî, ÷òî íàðÿäó ñ ïðèçíàêàìè ñõîäñòâà (÷èñëî ìèêðîòðóáî÷åê â ñëîå S 1 è ðàçìåð ëàìåëëÿðíîé ñòðóêòóðû), èìååòñÿ è öåëûé ðÿä ñóùåñòâåííûõ ðàçëè÷èé (òèï, ðàñïîëîaeåíèå è øèðèíà àïåðòóðû, î÷åðòàíèÿ ëàìåëëÿðíîé ñòðóêòóðû, îðèåíòàöèÿ áàçàëüíûõ òåëåö). Òàêèì îáðàçîì, ïîëó÷åííûå äàííûå íå äîêàçûâàþò áëèçêîãî ðîäñòâà ñåìåéñòâ Splachnaceae è Funariaceae è ìîãóò ÿâëÿòüñÿ äîïîëíèòåëüíûì àðãóìåíòîì ïðîòèâ îòíåñåíèÿ ýòèõ ñåìåéñòâ ê îäíîìó è òîìó aeå ïîðÿäêó. Abstract
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