Biology Forum › Genetics › DNA
- AuthorPosts
- September 30, 2009 at 12:20 am #11898
kareliagarcia76
ParticipantWhat are the mechanisms by which DNA is packaged into the nucleus and organized in such a way that it does not get ripped apart during cell division?
- September 30, 2009 at 1:50 am #93187
mith
Participantshouldn’t the dna be ripped apart during division?
- September 30, 2009 at 1:56 am #93190
kareliagarcia76
ParticipantI’m not sure. I’m thinking that its because it replicates itself rather than ripping apart.
- October 1, 2009 at 3:55 pm #93246
choozi
ParticipantDNA coil and supercoil and rotate around histone proteins to form nucleosomes.
- October 1, 2009 at 11:03 pm #93254
kolean
ParticipantI would say it is more like unzipped apart than ripped apart. And with all the proteins surrounding the DNA, it is more delicate than the word ripped conveys. More likely seduced apart by attracting forces……..lol.
Nucleosomes are the octamer of histones that the DNA wraps itself around 2 1/2 times around, with a linker DNA between these "beads". This "beads on a string" is then coiled into a 30 nm fiber with Histone 1 linking them together. This fiber can then be condensed into another fiber that may be modeled with chromatin proteins into heterochromatin, which is usually visually observed at the telomeres and at the centromeric regions. Chromosomes are then attached to the nuclear plasma membrane as an anchorage site.
- AuthorPosts
You must be logged in to reply to this topic.