• To ensure that only one sperm fertilizes an egg mechanisms are in place to prevent polyspermy, where multiple sperm try to fertilize the same egg. (biologysir.com)
  • In many species, the contents of only one sperm cell may enter the egg cell: a failure to prevent polyspermy results in the eventual failure of the embryo. (uconn.edu)
  • The prevention of polyspermy in sea urchins depends on a change in the electrical charge across the surface of the egg, which is caused by the fusion of the first sperm with the egg. (wikipedia.org)
  • 8. What is the term for the prevention of polyspermy? (biologysir.com)
  • In the frog Xenopus , the prevention of polyspermy is accomplished by a rapid depolarization of the egg cell membrane electrical potential, which has been shown through cross-species fertilization experiments to exert its effect on an unknown 'voltage-sensing' component of the sperm cell. (uconn.edu)
  • In biology, polyspermy describes the fertilization of an egg by more than one sperm. (wikipedia.org)
  • Some vertebrates that are both amniote or anamniote, including urodele amphibians, cartilaginous fish, birds and reptiles, undergo physiological polyspermy because of the internal fertilization of their yolky eggs. (wikipedia.org)
  • Unlike physiological polyspermy, monospermic fertilization deals with the analysis of the egg calcium waves, as this is the typical reproduction process in all species. (wikipedia.org)
  • While alkaloids often exert unique pharmacological effects on animal cells, exposure of sea urchin eggs to nicotine causes polyspermy at fertilization in a dose-dependent manner. (mdpi.com)
  • Following fertilization, the ZP undergoes changes described as 'hardening', which prevent multiple sperm from fertilizing the egg and thereby establish a block to polyspermy. (northwestern.edu)
  • These results provide a paradigm-shifting model in which fertilization-induced zinc sparks contribute to the polyspermy block by altering conformations of the ZP matrix. (northwestern.edu)
  • We investigated the relationship between ease of fertilization and susceptibility to polyspermy within and among three congeneric sea urchins. (bioone.org)
  • The results from laboratory studies indicate that, both within and among species, individuals and species that produce eggs capable of fertilization at relatively low sperm concentrations are more susceptible to polyspermy, whereas individuals and species producing eggs that require higher concentrations of sperm to be fertilized are more resistant to polyspermy. (bioone.org)
  • Mutations in PLCZ1 induce male infertility associated with polyspermy and fertilization failure. (urotoday.com)
  • This study aimed to investigate the effects of early and late cumulus cell removal on fertilization, polyspermy, embryonic development potential, blastocyst development, and clinical outcomes. (ecerm.org)
  • Fertilization, polyspermy, embryo quality, and pregnancy outcomes were not significantly different between both groups. (ecerm.org)
  • Early cumulus cell removal at 6 hours had no significant difference in fertilization, polyspermy, embryo development, or obstetric and perinatal outcomes compared to late removal. (ecerm.org)
  • Despite considerable technological advancements, polyspermy remains a significant challenge in in-vitro fertilization (IVF) procedures in pigs, disrupting normal embryonic development. (e-jarb.org)
  • Here, we aimed to determine whether optimal fertilization conditions reduce the polyspermy incidence in pigs. (e-jarb.org)
  • Collectively, these results demonstrate that various fertilization conditions, including modified co-culture period, active sperm separation, and culture medium volume, enhance fertilization efficiency and subsequent embryonic development by decreasing polyspermy occurrence. (e-jarb.org)
  • Electrical blocks are helpful in species where a very fast block to polyspermy is needed, due to the presence of many sperm arriving simultaneously at the egg surface, as occurs in animals such as sea urchins. (wikipedia.org)
  • The cell resulting from polyspermy, on the other hand, contains three or more copies of each chromosome-one from the egg and one each from multiple sperm. (wikipedia.org)
  • Physiological polyspermy happens when the egg normally accepts more than one sperm but only one of the multiple sperm will fuse its nucleus with the nucleus of the egg. (wikipedia.org)
  • The decline in the numbers of sperm that swim to the oviduct is one of two ways that prevents polyspermy in humans. (wikipedia.org)
  • This "electrical polyspermy block" is thought to result because a positively charged molecule in the sperm surface membrane is repelled by the positive charge at the egg surface. (wikipedia.org)
  • Such cytoskeletal changes appeared to render the eggs more receptive to sperm, as judged by the significant alleviation of polyspermy by latrunculin-A and mycalolide-B. In addition, our fluorimetric assay provided the first evidence that nicotine directly accelerates polymerization kinetics of G-actin and attenuates depolymerization of preassembled F-actin. (mdpi.com)
  • Developmental failure caused by excess sperm (polyspermy) is thought to be an important mechanism driving the evolution of gamete-recognition proteins, reproductive isolation, and speciation in marine organisms. (bioone.org)
  • However, these theories assume that there is heritable variation in the susceptibility to polyspermy and that this variation is related to the overall affinity between sperm and eggs. (bioone.org)
  • The defensive response may be beneficial in preventing polyspermy, when an egg is fertilized by more than one sperm and cannot develop. (phys.org)
  • Although the 6 h sperm-free cultured group had a higher penetration rate than the 5 h cultured group, the polyspermy rate significantly increased in the 6 h sperm-free cultured group. (e-jarb.org)
  • Finally, we review recent progress made in elucidating the mechanisms that reduce polyspermy and ensure that eggs normally fuse with only a single sperm. (york.ac.uk)
  • With the zona pellucida, and the acrosome and cortical reactions fertilisation by multiple sperm (dispermy or polyspermy) is prevented. (pediagenosis.com)
  • Physiological polyspermy is present in some species of vertebrates and invertebrates. (wikipedia.org)
  • Some species utilize physiological polyspermy as the proper mechanism for developing their offspring. (wikipedia.org)
  • This induction plays a very critical role in both physiological polyspermy and monomeric polyspermy species. (wikipedia.org)
  • Species that undergo physiological polyspermy have polyploidy-preventing mechanisms that act inside the egg. (wikipedia.org)
  • Using a fluorescent PI(4,5)P 2 sensor and heterologously expressed Xenopus VSPs, I show that Xl-VSP1 and Xt-VSP activate in the physiological range of voltages known to block polyspermy in Xenopus , but that Xl-VSP2 activates at more positive potentials. (uconn.edu)
  • Animals such as sea urchins have a two-step polyspermy prevention strategy, with the fast, but transient, electrical block superseded after the first minute or so by a more slowly developing permanent mechanical block. (wikipedia.org)
  • Don R. Levitan , Casey P. terHorst , and Nicole D. Fogarty "THE RISK OF POLYSPERMY IN THREE CONGENERIC SEA URCHINS AND ITS IMPLICATIONS FOR GAMETIC INCOMPATIBILITY AND REPRODUCTIVE ISOLATION," Evolution 61(8), 2009-2016, (1 August 2007). (bioone.org)
  • In species without an electrical block, polyspermy is usually prevented by secretion of materials that establish a mechanical barrier to polyspermy. (wikipedia.org)
  • This is quite different from the normal polyspermy block on the outside of the egg. (wikipedia.org)
  • A the slow block to polyspermy. (justaaa.com)
  • Electrical polyspermy blocks operate in many animal species, including frogs, clams, and marine worms, but not in the several mammals that have been studied (hamster, rabbit, mouse). (wikipedia.org)
  • As both haploid induction and polyspermy are valuable breeding aims, our results open new avenues for accelerated generation of climate adapted cultivars. (elifesciences.org)
  • Polyspermy thus has the potential to harness previously incompatible climate adapted wild varieties for plant breeding. (elifesciences.org)
  • Capitalizing on a high-throughput polyspermy assay, we in addition show that the double mutant exhibits a three-fold increase in polyspermy frequencies. (elifesciences.org)
  • Thus, MATER plays an important role in tethering cortical granules in the egg cortex to ensure timely exocytosis of ovastacin in the post-fertilization block to polyspermy. (nih.gov)
  • By creating a new barrier and destroying the initial interface between sperm and egg, the cortical reaction prevents polyspermy, or the fertilization of a single egg by multiple sperm. (lacteoscienelac.com)
  • This is thought to be the morphological expression of the zonal reaction, and the cortical and zonal reactions may provide a block to polyspermy. (ehd.org)
  • Diagrama mostrando reação acrosomal, fusão de membranas de ovo e esperma e bloqueio cortical para polyspermy, desenho rotulado. (alilamedicalmedia.com)
  • Polyubiquitin chain recognition activities associated with the sperm acrosomal proteasome could also contribute to anti-polyspermy control after sperm-egg fusion. (edu.au)
  • Physiological polyspermy happens when the egg normally accepts more than one sperm but only one of the multiple sperm will fuse its nucleus with the nucleus of the egg. (wikipedia.org)
  • Physiological polyspermy is present in some species of vertebrates and invertebrates. (wikipedia.org)
  • Some species utilize physiological polyspermy as the proper mechanism for developing their offspring. (wikipedia.org)
  • This induction plays a very critical role in both physiological polyspermy and monomeric polyspermy species. (wikipedia.org)
  • Species that undergo physiological polyspermy have polyploidy-preventing mechanisms that act inside the egg. (wikipedia.org)
  • Monospermy and Physiological Polyspermy. (cravencountryjamboree.com)
  • The decline in the numbers of sperm that swim to the oviduct is one of two ways that prevents polyspermy in humans. (wikipedia.org)
  • The calcium wave that prevents polyspermy also causes A. the sperm to lose its tail. (lacteoscienelac.com)
  • This, thus, prevents the polyspermy and ensures that only one sperm can fertilise an ovum. (lacteoscienelac.com)
  • In general, the entry of more than two spermatozoa into the egg cytoplasm, referred to as polyspermy, causes aberrant effects on meiosis completion or embryo development and hence embryonic death, due mainly to excess male centrosomes delivered into the egg. (cravencountryjamboree.com)
  • When polyspermy occurs, multipolar or extra miotic spindles form, which stop the development of the fertilized egg by causing faulty segregation of chromosomes during cell division. (lacteoscienelac.com)
  • In polyspermy, an abnormal number of sperm fertilize a single egg, resulting in an embryo with an abnormal set of chromosomes. (lacteoscienelac.com)
  • Polyspermy, while physiologically possible in some species of vertebrates and invertebrates, is a lethal condition for the human zygote. (lacteoscienelac.com)
  • The purpose of this review is to open a debate as to whether or not oocytes actively repel supernumerary sperm or in nature final sperm : oocyte ratios are so low that polyspermy preventing mechanisms are not necessary. (lacteoscienelac.com)
  • What is polyspermy How do you avoid that what are the consequences of polyspermy? (lacteoscienelac.com)
  • The cell resulting from polyspermy, on the other hand, contains three or more copies of each chromosome-one from the egg and one each from multiple sperm. (wikipedia.org)
  • Preventing polyspermy: Although many sperm attach to the coats surrounding the egg, it is important that only one sperm fuses with the egg plasma membrane and delivers its nucleus into the egg. (lacteoscienelac.com)