Results 321 to 330 of about 111,170 (357)
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MEIOSIS IN COPRINUS: VI. THE CONTROL OF THE INITIATION OF MEIOSIS
Canadian Journal of Genetics and Cytology, 1974Meiosis in Coprinus lagopus is normally initiated at night under normal diurnal conditions. This timing can be shifted to 0900-1000 h by using a 16h light-8h dark regime with the light cycle commencing at 1600 h. For the initiation of meiosis, C. lagopus is temperature sensitive (35 C) under continuous light. The temperature sensitivity can be overcome
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Journal of Experimental Zoology, 1999
During oogenesis the oocyte is arrested in meiosis twice. First at prophase I, then a second time at metaphase I in many invertebrates and in metaphase II in the vast majority of vertebrates. Meiosis resumption is triggered by the sperm. This article examines mechanisms that cause oocytes' arrest in meiosis and how spermatozoa help the oocyte to get ...
Martin Wilding +2 more
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During oogenesis the oocyte is arrested in meiosis twice. First at prophase I, then a second time at metaphase I in many invertebrates and in metaphase II in the vast majority of vertebrates. Meiosis resumption is triggered by the sperm. This article examines mechanisms that cause oocytes' arrest in meiosis and how spermatozoa help the oocyte to get ...
Martin Wilding +2 more
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1990
Repetition is the only form of permanence that nature can achieve. George Santayana The essential requirement of meiosis is the regular segregation of homologous chromosomes or chromosome regions. Only in this way is it possible to produce the genetically balanced gametes necessary to sustain development.
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Repetition is the only form of permanence that nature can achieve. George Santayana The essential requirement of meiosis is the regular segregation of homologous chromosomes or chromosome regions. Only in this way is it possible to produce the genetically balanced gametes necessary to sustain development.
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Nature, 1933 FROM observations made in this laboratory by S. G. Smith, E. Marie Hearne, Jane D. Spier, J. M. Armstrong, A. W. S. Hunter, and me on meiosis and both haploid and diploid mitosis in Trillium, Matthiola, a number of cereals and grasses, and in grasshoppers, it can be shown that, at all stages of mitosis and meiosis, chromosome threads are attracted in ...
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1980
Most of the cell divisions that occur in the germline are mitotic: a series of over 30 in females and over 200 in males (Chapter 9). It is only the final two divisions that are meiotic. What mediates the switch from mitosis to meiosis, and by what mechanisms do all oogonia switch almost simultaneously during fetal life while only one of the two ...
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Most of the cell divisions that occur in the germline are mitotic: a series of over 30 in females and over 200 in males (Chapter 9). It is only the final two divisions that are meiotic. What mediates the switch from mitosis to meiosis, and by what mechanisms do all oogonia switch almost simultaneously during fetal life while only one of the two ...
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Sex, Meiosis and Multicellularity
Acta Biotheoretica, 1997The origin and progress of multicellularity, which is one of the crucial steps in the evolution of life, remains unclear and stringent phylogenetic reconstruction of the process is difficult. However, further theoretical considerations of the problem could be useful for the creation of a verifiable hypothesis.
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Crossing and zipping: molecular duties of the ZMM proteins in meiosis
Chromosoma, 2019A. Pyatnitskaya +2 more
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1961
Publisher Summary The essential characteristics of meiosis are pairing, crossing over, and reduction in chromosome number. Fertilization and meiosis are compensating events; a failure of one or the other causes a breakdown in the orderly system of sexual reproduction.
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Publisher Summary The essential characteristics of meiosis are pairing, crossing over, and reduction in chromosome number. Fertilization and meiosis are compensating events; a failure of one or the other causes a breakdown in the orderly system of sexual reproduction.
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2007
STUDY HINTS Genes are located on chromosomes, and the stable manner in which chromosomes are first replicated and then distributed to daughter cells during cell division is the basis for genetic inheritance. Since much of genetic theory is based on the behavior of chromosomes and the genes they carry, it is very important to understand clearly how ...
David S. Durica +3 more
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STUDY HINTS Genes are located on chromosomes, and the stable manner in which chromosomes are first replicated and then distributed to daughter cells during cell division is the basis for genetic inheritance. Since much of genetic theory is based on the behavior of chromosomes and the genes they carry, it is very important to understand clearly how ...
David S. Durica +3 more
openaire +2 more sources