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

Moderators: Leonid, amiradm, BioTeam

Post Reply
Posts: 4
Joined: Mon Jun 21, 2010 9:52 am


Post by ezahemalf » Fri Sep 10, 2010 7:10 am

help, anyone!!! :cry: i need this for my biology homework:

1. explain why the cells replicate their DNA before they divide to provide identical genetic information to daughter cells

2. Do cells usually decode nucleotides in one direction only or in either direction?

User avatar
Inland Taipan
Inland Taipan
Posts: 5694
Joined: Mon Sep 14, 2009 7:12 pm

Post by JackBean » Fri Sep 10, 2010 8:42 am

1. think about it. What would happen, if they did not replicate the DNA? :roll:

2. just look into ANY MolBio book :roll:

Cis or trans? That's what matters.

Posts: 345
Joined: Thu Jun 25, 2009 3:15 am

Post by kolean » Fri Sep 10, 2010 2:19 pm

1. the term 'identical' is very important when dividing the DNA into two daughter cells.

2.this could be a trick question. the RNA polymerase can only read in the 3' to 5' direction of DNA, which could be the east to west direction on the one strand, while west to east on the other strand, since DNA is double stranded (not single stranded like RNA - that is only because double-stranded RNA gets cleaved).

'Decode' nucleotides usually means protein coding genes I suppose, but there are alot of regulatory RNA out there being discovered right now that need to be decoded too.

Posts: 1278
Joined: Thu Mar 02, 2006 5:29 pm
Location: New York, USA

Post by Darby » Fri Sep 10, 2010 11:59 pm

For number 2, think of the difficulty of having a "readable" code in one direction AND in the complement across from it. It's amazing that it ever happens.

Post Reply

Who is online

Users browsing this forum: No registered users and 2 guests