Asked by: Alessandro Bertscheasked in category: General Last Updated: 21st January, 2020
What is Polyspermy how it is prevented?
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Considering this, how is Polyspermy prevented quizlet?
Polyspermy is the double fertilization of an ovum by two sperm. It is prevented by 3 methods during fertilization: 1) The intracellular wave of Ca2+ that travels across the oocyte membrane and causes hyper polarization after fusion of the sperm and oocyte membranes.
Secondly, what is Polyspermy and why is it bad? Polyspermy is bad because, in addition to the extra set of chromosomes, a sea urchin sperm donates a centriole. The presence of additional centrioles during the first cell division will result in additional cleavage furrows and incorrect partitioning of the chromosomes (Fig. 7.21).
One may also ask, why is Polyspermy block necessary?
It is thought that electrical blocks evolved in those 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.
Do humans have fast block to Polyspermy?
The “oocyte membrane block” or so-called “fast block” to polyspermy occurs in seconds [6–8]; however, it was unlikely to be involved in “fast block” to polyspermy in the fertilization process in mammals .