From: John Mikes <jami...@gmail.com> To: everything-list@googlegroups.com Sent: Tuesday, April 7, 2015 2:03 PM Subject: Re: Histones (proteins that form the scaffolding around which DNA wraps itself may also themselves be involved in heredity processes Apologies: MITOCHONDRIUM - I S - and mitochondria -are. JM
On Tue, Apr 7, 2015 at 4:14 PM, John Mikes <jami...@gmail.com> wrote: Liz:"passed on" - do you mean survives AS IS? I think whatever is added incubates into the complexity of the new creature into fitting, not 'as was' in the mother. And- I think mitochondria IS a cell within the larger one in symbiotic life. Chris is most likely right: FROM THE MOTHER only. And it is adjusted into the new complexity as well. This is the reason why mitochondria are used as a yardstick to measure the natural rate of mutation (e.g. the genetic drift). Because all animals exclusively get their own mitochondria from their mother -- e.g. NOT by sexual reproduction, which effectively is a shuffling of the genetic heritage of both portions of both parents DNA. The mitochondria DNA instead only ever comes from the maternal line and for this reason it makes a good genetic clock. A clock that can be used to estimate how old a species is, or that can tell a story of how a species almost went extinct some 70,000 years ago -- as happened to our own species. The reason e know this is by studying the genetic diversity of human mitochondrial DNA.Interestingly the Y chromosome, which all males of a species carry and exclusively get from the paternal side, can also function as a yardstick, again because it is unaffected by sexual reproduction. If an offspring has the Y chromosome (e.g. is a male) it got it from its father and never ever got it from its mother. For all our other chromosomes what we get is the sexually reshuffled recombined deck of cards, some of which came from each parent.Does this make any sense?Chris JM On Tue, Apr 7, 2015 at 12:18 AM, LizR <lizj...@gmail.com> wrote: Anything in the egg cell, or donated at any point during gestation from the mother (in mammals, at least) can be passed on, I assume. (What about mitochondria?) -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.