Meiotic abnormalities

Down syndrome incidence in humans increases dramatically with maternal age. This is mainly the result of increased meiotic errors, but factors such as differences in abortion rate may play a role as well. Since the meiotic error rate increases almost exponentially after a certain age, its contribution to the overall incidence aneuploidy may mask the contribution of other processes.

8p vinarcissa 21-03-2023 5 1   Download

Meiotic abnormalities lead to morphological and genetic variations which caused not only to evolution but also intraspecific reproductive barriers. During present study of detailed meiotic course in dicotyledonous plants sampled from Indian cold deserts, various meiotic abnormalities have been detected.

11p viharuno2711 24-04-2020 25 0   Download

The genotoxic effects of 2 heavy metals (mercury chloride and cadmium chloride) on the gametic cells of 6 inbred lines of maize were tested in terms of cytological abnormalities. Meiosis was normal under control conditions. During the treatments with mercury and cadmium there was a concentration-dependent increase in meiotic abnormalities in all the inbred lines.

8p vibasque27 27-03-2019 16 1   Download

Bromus Section Ceratochloa includes temperate forage species. South American species form a morphologically very variable hexaploid complex (2n = 6x = 42), with a controversial taxonomic classification. Reproductive biology has been studied in several of them, but the number of analyzed plants has seldom been reported.

7p vikimsa 22-02-2019 11 1   Download

Genotoxic effects of two heavy metals viz. mercury (Hg) and cadmium (Cd) on somatic and gametic cells of soybean were investigated. Seeds were treated with different doses of these heavy metals.

6p vitamix 15-02-2019 15 1   Download

This book contains four parts with 16 chapters. Firstly, an optimal stimulation scheme  for  ovaries,  particularly  natural  and  minimal  stimulation  of  ovaries,  has  been  discussed  in  the  first  part.  Then,  one  paper  analyzed  that  how  many  oocytes  per  retrieval will be  the best  for human IVF practice. If one stimulation scheme produces  too  many  eggs,  it  often  results  in  hyperstimulation  syndrome.  Thus,  a  chapter  reviewed  hyperstimulation  syndrome  diagnosis,  prevention  and  treatment.

148p yeutinh98 22-09-2012 63 8   Download

Aldosterone: Enhances Na+ reabsorption at the collecting duct of the kidney Aneuploidies: Abnormal numbers of chromosomes that may occur as a consequence of abnormal meiotic division of chromosomes in gamete formation Antidiuretic hormone (arginine vasopressin): Acts to conserve water by increasing the permeability of the collecting duct of the kidney Blastocyst: At the 8- to 16-cell stage, the blastomere develops a central cavity and becomes a blastocyst. The cells on the outer layer differentiate to become trophoblasts. ...

60p lananhanh123 27-08-2011 46 2   Download