Can someone explain synapsis to me please?

Question

I understand that it occurs during the Prophase I and that it is the coming together of chromosomes but how exactly does it happen and why does it form a bivalent. Thank you for your help

David H - yes but how does this whole activated electricity make it happen, it may seem like a very stupid question but i'm only an A-level student and we have only just started looking at meiosis properly thanks

Answer 1

Well, as it says on wikipedia "currently unexplained" I expect that means we don't know exactly how it happens. Why it happens, the ultimate reason is that it seems to be the simplest way to sort the chromosomes and to make sure each cell gets one complete set of chromosomes and not an odd mix. If that's not the case any progeny of those cells probably won't work, and anyway without that heritability of traits would be hard to maintain.

If you want more details try medline or web of science and look for articles about current research on that subject. Type in: synapsis meiosis review, and you probably get a bunch of useful papers. Maybe try this for a start: http://www.genesdev.org/cgi/content/full/20/15/1986.

Or you may end up researching that for a thesis one day...

Anyway, it doesn't have to do anything with electricity, connections between nerve cells are synapses, but that's not what you are concerned with at the moment.

Answer 2

Synapsis is the currently unexplained phenomenon of two homologous chromosomes coming together and lining up side-by-side resulting in a bivalent (also known as a tetrad), or two homologous chromosomes that stay in close association during the first two phases of meiosis I (the stages being Prophase I and Metaphase I). As the two chromosomes synapse, they come closer together and when their chromatids intertwine, segments of chromatids (also known as genes) break apart and are exchanged, in a process known as a cross-over, an exchange of genetic material between two homologous chromosomes.

Answer 3

Synapsis is the currently unexplained phenomenon of two homologous chromosomes coming together and lining up side-by-side resulting in a bivalent (also known as a tetrad), or two homologous chromosomes that stay in close association during the first two phases of meiosis I (the stages being Prophase I and Metaphase I). As the two chromosomes synapse, they come closer together and when their chromatids intertwine, segments of chromatids (also known as genes) break apart and are exchanged, in a process known as a cross-over, an exchange of genetic material between two homologous chromosomes.

Answer 4

the brain activates electricity, need i say more