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Index of Subjects --Apple-Mail-24--834392260 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed On 21-Apr-07, at 4:45 PM, Gerald Ruderman wrote: > > Chris, > > Thanks. The Wikipedia entry for triploid left me clueless. Parthenogenesis is a form of asexual reproduction in which females produce eggs that develop without fertilization. Beyond that, you need to know what a chromosome is. Normal individuals have pairs of chromosomes; females have XX; males have XY. Two chromosomes = diploid. There are some females that have three chromosomes, XXX. three chromosomes = triploid, etc. (see polyploidy below). Such females can produce self-fertilized eggs. Normally meiosis (cell division to produce germ cells) produces haploid (=1/2 the normal number of chromosomes) cells, but it works somewhat differently in triploid individuals. These individuals which develop from self-fertilized eggs are genetic duplicates of their mothers (clones) and create a line of female-only individuals. For further information take a look at: http://en.wikipedia.org/wiki/Meiosis http://en.wikipedia.org/wiki/Polyploidy Wikipedia is a useful way to learn things since all the words shown in blue are linked to entries that explain what they mean. Parthenogenesis is not that complicated a concept, but you need to know some basic genetics to get the gist of it. Best wishes, Chris > > c.majka@ns.sympatico.ca wrote: >> Hi Gerald, >> >> These salamanders reproduce parthenogenetically. There is a detailed >> description of the process of parthenogenesis in the Wikipedia at: >> >> http://en.wikipedia.org/wiki/Parthenogenesis >> >> I'm no longer 14, but it should not be difficult to understand so >> long >> as one knows what a chromosome is. >> >> Best wishes, >> >> Chris _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._. _. Christopher Majka - Nova Scotia Museum of Natural History 1747 Summer Street, Halifax, Nova Scotia, Canada B3H 3A6 (902) 424-6435 Email <c.majka@ns.sympatico.ca> _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._. _. --Apple-Mail-24--834392260 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=ISO-8859-1 <HTML><BODY style=3D"word-wrap: break-word; -khtml-nbsp-mode: space; = -khtml-line-break: after-white-space; "><BR><DIV><DIV>On 21-Apr-07, at = 4:45 PM, Gerald Ruderman wrote:</DIV><BR = class=3D"Apple-interchange-newline"><BLOCKQUOTE type=3D"cite"><DIV = style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: 0px; = margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style=3D"margin-top: = 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; = ">Chris,</DIV><DIV style=3D"margin-top: 0px; margin-right: 0px; = margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV = style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: 0px; = margin-left: 0px; ">Thanks. The Wikipedia entry for triploid left me = clueless.</DIV></BLOCKQUOTE><DIV><BR = class=3D"khtml-block-placeholder"></DIV><DIV>Parthenogenesis is a form = of asexual reproduction in which females produce eggs that develop = without fertilization.</DIV><DIV><BR = class=3D"khtml-block-placeholder"></DIV><DIV>Beyond that, you need to = know what a chromosome is. Normal individuals have pairs of chromosomes; = females have XX; males have XY. Two chromosomes =3D diploid. There are = some females that have three chromosomes, XXX. three chromosomes =3D = triploid, etc. (see polyploidy below). Such females can produce = self-fertilized eggs. Normally meiosis (cell division to produce germ = cells) produces haploid (=3D1/2 the normal number of chromosomes) cells, = but it works somewhat differently in triploid individuals. These = individuals which develop from self-fertilized eggs are genetic = duplicates of their mothers (clones) and create a line of female-only = individuals.</DIV><DIV><BR = class=3D"khtml-block-placeholder"></DIV><DIV>For further information = take a look at:</DIV><DIV><BR = class=3D"khtml-block-placeholder"></DIV><DIV><A = href=3D"http://en.wikipedia.org/wiki/Meiosis">http://en.wikipedia.org/wiki= /Meiosis</A></DIV><DIV><A = href=3D"http://en.wikipedia.org/wiki/Polyploidy">http://en.wikipedia.org/w= iki/Polyploidy</A></DIV><DIV><BR = class=3D"khtml-block-placeholder"></DIV><DIV>Wikipedia is a useful way = to learn things since all the words shown in blue are linked to entries = that explain what they mean. Parthenogenesis is not that complicated a = concept, but you need to know some basic genetics to get the gist of = it.</DIV><DIV><BR class=3D"khtml-block-placeholder"></DIV><DIV>Best = wishes,</DIV><DIV><BR = class=3D"khtml-block-placeholder"></DIV><DIV>Chris</DIV><BR><BLOCKQUOTE = type=3D"cite"><DIV style=3D"margin-top: 0px; margin-right: 0px; = margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV = style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: 0px; = margin-left: 0px; "><A = href=3D"mailto:c.majka@ns.sympatico.ca">c.majka@ns.sympatico.ca</A> = wrote:</DIV> <BLOCKQUOTE type=3D"cite"><DIV style=3D"margin-top: 0px; = margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Hi = Gerald,</DIV><DIV style=3D"margin-top: 0px; margin-right: 0px; = margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV = style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: 0px; = margin-left: 0px; ">These salamanders reproduce parthenogenetically. = There is a detailed</DIV><DIV style=3D"margin-top: 0px; margin-right: = 0px; margin-bottom: 0px; margin-left: 0px; ">description of the process = of parthenogenesis in the Wikipedia at:</DIV><DIV style=3D"margin-top: = 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; = min-height: 14px; "><BR></DIV><DIV style=3D"margin-top: 0px; = margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><A = href=3D"http://en.wikipedia.org/wiki/Parthenogenesis">http://en.wikipedia.= org/wiki/Parthenogenesis</A></DIV><DIV style=3D"margin-top: 0px; = margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: = 14px; "><BR></DIV><DIV style=3D"margin-top: 0px; margin-right: 0px; = margin-bottom: 0px; margin-left: 0px; ">I'm no longer 14, but it should = not be difficult to understand so long</DIV><DIV style=3D"margin-top: = 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">as one = knows what a chromosome is.</DIV><DIV style=3D"margin-top: 0px; = margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: = 14px; "><BR></DIV><DIV style=3D"margin-top: 0px; margin-right: 0px; = margin-bottom: 0px; margin-left: 0px; ">Best wishes,</DIV><DIV = style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: 0px; = margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style=3D"margin-top: = 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; = ">Chris</DIV> </BLOCKQUOTE></BLOCKQUOTE></DIV><BR><DIV> <P = style=3D"margin: 0.0px 0.0px 0.0px 0.0px"><FONT face=3D"Times" size=3D"3" = style=3D"font: 12.0px = Times">_._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._= ._._._.</FONT></P> <P style=3D"margin: 0.0px 0.0px 0.0px 0.0px"><FONT = face=3D"Times" size=3D"3" style=3D"font: 12.0px Times">Christopher Majka = - Nova Scotia Museum of Natural History</FONT></P> <P style=3D"margin: = 0.0px 0.0px 0.0px 0.0px"><FONT face=3D"Times" size=3D"3" style=3D"font: = 12.0px Times">1747 Summer Street, Halifax, Nova Scotia, Canada<SPAN = class=3D"Apple-converted-space">=A0 </SPAN>B3H 3A6</FONT></P> <P = style=3D"margin: 0.0px 0.0px 0.0px 0.0px"><FONT face=3D"Times" size=3D"3" = style=3D"font: 12.0px Times">(902) 424-6435 <SPAN = class=3D"Apple-converted-space">=A0 </SPAN>Email <<A = href=3D"mailto:c.majka@ns.sympatico.ca">c.majka@ns.sympatico.ca</A>></F= ONT></P> <P style=3D"margin: 0.0px 0.0px 0.0px 0.0px"><FONT face=3D"Times"= size=3D"3" style=3D"font: 12.0px = Times">_._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._= ._._._.</FONT></P> </DIV><BR></BODY></HTML>= --Apple-Mail-24--834392260--
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