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Start Over Subject 2 Subject Česko

32. Karyotypes of central European spiders of the genera Arctosa, Tricca, and Xerolycosa (Araneae: Lycosidae)

Creator:
Dolejš, Petr, Kořínková, Tereza, Musilová, Jana, Opatová, Věra, Kubcová, Lenka, Buchar, Jan, and Král, Jiří
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, entomologie, Česko, Rakousko, Czechia, Austria, Lycosidae, spiders, karyotype, sex chromosomes, meiosis, constitutive heterochromatin, nucleolar organizer region, 2, and 59
Language:
English
Description:
The aim of this study was to characterize karyotypes of central European spiders of the genera Arctosa, Tricca, and Xerolycosa (Lycosidae) with respect to the diploid chromosome number, chromosome morphology, and sex chromosomes. Karyotype data are reported for eleven species, six of them for the first time. For selected species the pattern in the distributions of the constitutive heterochromatin and the nucleolar organizer regions (NORs) was determined. The silver staining technique for detecting NORs of lycosid spiders was standardized. The male karyotype consisted of 2n = 28 (Arctosa and Tricca) or 2n = 22 (Xerolycosa) acrocentric chromosomes. The sex chromosome system was X1X20 in all species. The sex chromosomes of T. lutetiana and X. nemoralis showed unusual behaviour during late diplotene, namely temporary extension due to decondensation. C-banding technique revealed a small amount of constitutive heterochromatin at the centromeric region of the chromosomes. Two pairs of autosomes bore terminal NORs. Differences in karyotypes among Arctosa species indicate that the evolution of the karyotype in this genus involved autosome translocations and size changes in the sex chromosomes. Based on published results and those recorded in this study it is suggested that the ancestral male karyotype of the superfamily Lycosoidea consisted of 28 acrocentric chromosomes. and Petr DOLEJŠ, Tereza KOŘÍNKOVÁ, Jana MUSILOVÁ, Věra OPATOVÁ, Lenka KUBCOVÁ, Jan BUCHAR, Jiří KRÁL.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

33. Kde přežít v těžkých časech?: refugia epifytických lišejníků

Creator:
Malíček, Jiří and Syrovátková, Lada
Format:
bez média and svazek
Type:
article, text, články, journal articles, model:article, and TEXT
Subject:
Biologické vědy, biologie, lichenologie, lišejníky, životní prostředí, bioindikátory, lichenes, biology, lichenology, environment, bioindicators, Česko, epifytické lišejníky, refugia, 2, and 57/59
Language:
Czech
Description:
Epifytické lišejníky jakožto citlivé bioindikátory rychle reagují na změny v životním prostředí, zvláště na znečištění ovzduší. V období kyselých dešťů došlo v ČR k zásadní proměně epifytických společenstev. Existují však místa, která byla ovlivněna jen v menší míře a doposud zde přežívají vzácné druhy. Takové lokality můžeme považovat za novodobá refugia., Epiphytic lichens as sensitive bioindicators reflect changes in the environment (e.g. air pollution) very quickly. Acid rains occurring in the second half of the 20th century have considerably affected the epiphytic biota of the Czech Republic. However, there are several places, which have been less influenced and where rare lichens still survive. We consider such places to serve as recent refugia., and Jiří Malíček, Lada Syrovátková.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

37. Mechorosty České republiky

Creator:
Jan Kučera
Format:
print
Type:
article, články, model:article, and TEXT
Subject:
Botanika, flóra, mechy, mechorosty, Česko, 2, and 58
Language:
Czech
Description:
Bryophytes, with their more than 860 species, represent more than a quarter of higher plants native to the CR. They can reveal much more about the ecosystems they live in than we would expect, as their physiological contact with the surroundings is much closer than that of the vascular plants. and Jan Kučera.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

38. Medvěd hnědý, jeho vyhubení a návrat do naší přírody. 1

Creator:
Jan Andreska
Format:
print
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, medvěd hnědý, vyhubení, Česko, 2, and 59
Language:
Czech
Description:
Detailed knowledge of the circumstances behind the extermination of particular animal species is a key premise for their eventual return, reintroduction and ongoing preservation. Data on the presence of the Brown Bear (Ursus arctos) in the Czech landscape are usually limited to simple entries about the day and place where the last specimens in particular (usually mountainous) regions were slain. Demand for more precise data, especially regarding the last documented presence of bear cubs, has emerged in respect of the recently discovered ability of bears to migrate over long distances. The newly collected data allowed the author to present amuch more complete historical view of the process of extermination of the Brown Bear in the Czech territory. and Jan Andreska.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

39. Medvěd hnědý, jeho vyhubení a návrat do naší přírody. II

Creator:
Jan Andreska
Format:
print
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, medvěd hnědý, Česko, 2, and 59
Language:
Czech
Description:
The prolonged survival of the Brown Bear (Ursus arctos) population in the Bohemian Forest was largely possible due to the protec tion of this animal, which was considered a rare and desirable trophy. Consequently the bear was able to survive in the Bohemian Forest for a hundred years longer than in the Ore Mountains. Isolated populations in the Sudetes survived in Moravia, and the last specimens were hunted down in the 1740s. Bears hunted down during the 19th century in the Beskydy Mts. can almost certainly be considered casual migrants from the Slovak part of this mountain range. The return of bears to the territory of Moravia and Silesia corresponds with the consolidation of the Slovak population due to the protection introduced in 1932. and Jan Andreska.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

40. Mezinárodní rok biodiverzity v ČR - rok jako každý jiný

Creator:
Petřík, Petr
Type:
article, články, model:article, and TEXT
Subject:
Obecná ekologie, biodiverzita, ochrana přírody, politiky Evropské unie, biodiversity, nature conservation, European policies, Česko, Czechia, 2, and 574
Language:
Czech
Description:
In November 2009, the United Nations declared 2010 to be the International Year of Biodiversity. It has been a celebration of life on earth and of the value of biodiversity for our lives. The world has been invited to take action in 2010 to safeguard biodiversity, i. e., the variety of life on earth. Throughout the year countless initiatives were organized to disseminate information, promote the protection of biodiversity and encourage organizations, institutions, companies and individuals to take direct action to reduce the constant loss of biological diversity worldwide. and Petr Petřík.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public