Login

Join for Free!
114359 members


DNA - mitosis - chromosome - chromatid

Genetics as it applies to evolution, molecular biology, and medical aspects.

Moderator: BioTeam

DNA - mitosis - chromosome - chromatid

Postby myname » Sat Nov 06, 2010 1:06 pm

Hello! :)

I have a simple question regarding DNA and mitosis which will be way to simple for you, I suppose, but I just didn't know where else to ask.

Does a chromatid consist of one DNA double helix and therefore a chromosome of two DNA double helices? Then during the mitosis the chromosme is split into two chromatids. Consequently there would be each on DNA double helix in each of the two cells that developed from one.

Or does a chromsome only consist of one double helix which is split into 2 parts during the mitosis?


I'm thankful for any help!!! :)
myname
Garter
Garter
 
Posts: 3
Joined: Sat Nov 06, 2010 12:24 pm

Postby JackBean » Sat Nov 06, 2010 1:27 pm

the double helix gets never separated
(of course besides replication and transcription ;)
http://www.biolib.cz/en/main/

Cis or trans? That's what matters.
User avatar
JackBean
Inland Taipan
Inland Taipan
 
Posts: 5665
Joined: Mon Sep 14, 2009 7:12 pm

Postby myname » Sat Nov 06, 2010 1:31 pm

Consequently a 2-chromatid-chromosome consists of two DNA double helices I suppose...
myname
Garter
Garter
 
Posts: 3
Joined: Sat Nov 06, 2010 12:24 pm


Re: DNA - mitosis - chromosome - chromatid

Postby Jordanw21 » Sun Nov 07, 2010 2:40 pm

Before a cell goes into mitosis, it must go through interphase first, where replication of the DNA occurs. There are now two copies of each strand, each of which forms one chromatid in the chromosome. Now keep in mind, the sister chromatids are two separate DNA molecules, but they are connected by the centromere to form the chromosome. Anaphase is when the two are separated, so that after telophase and cytokinesis, each daughter cell has one of each chromatid, and the sister chromatids will be exact copies, except for any random mutations of course.
Jordanw21
Garter
Garter
 
Posts: 5
Joined: Thu Nov 04, 2010 5:29 pm

Postby myname » Sun Nov 07, 2010 4:02 pm

Thanks. (:
myname
Garter
Garter
 
Posts: 3
Joined: Sat Nov 06, 2010 12:24 pm


Return to Genetics

Who is online

Users browsing this forum: No registered users and 2 guests

cron