Question

from chromatin, two major processes are needed to prepare for dna replication. watch the video at right - what processes are needed before new dna can be made? select all that apply. dna has to be coiled dna has to be in chromosome form dna has to be uncoiled dna has to be destroyed bonds between bases have to be broken bonds between phosphates and sugars in the dna backbone have to be broken

Explanation:

To prepare chromatin for DNA replication:

• DNA in chromatin is coiled; it needs to be uncailed (uncoiled) to access the DNA strands (so "DNA has to be uncailed" is correct, "DNA has to be coiled" is incorrect as coiled chromatin is too compact).
• "DNA has to be in chromosome form" is incorrect because chromatin (less condensed) is modified, not kept as chromosomes (highly condensed).
• "DNA has to be destroyed" is wrong—replication makes new DNA, not destroys it.
• Bonds between bases (hydrogen bonds) have to be broken to separate the two DNA strands (a key step in replication, like in DNA helicase action).
• Bonds between phosphates and sugars in the backbone are not broken in replication initiation (that would fragment DNA, which isn’t done here).

So the correct options are the ones where DNA is uncoiled and base bonds are broken.

Answer:

• DNA has to be uncailed
• Bonds between bases have to be broken