Which chemical process causes RNA or DNA replication?

AI Thread Summary
DNA and RNA possess unique molecular structures that enable self-replication, driven by a combination of chemical phenomena rather than any singular magical process. The key mechanism for DNA replication involves the splitting of the DNA molecule by helicases, which break the hydrogen bonds between base pairs. A-T pairs, with only two hydrogen bonds, are easier to separate than G-C pairs, which have three, leading to replication typically occurring in regions rich in A-T pairs. The process of DNA replication is tightly regulated during the cell cycle, specifically in the S phase, with checkpoints controlled by proteins such as cyclins and cyclin-dependent kinases. Cyclins fluctuate in concentration throughout the cell cycle, peaking at the start of the S phase, suggesting a complex regulatory mechanism that governs their cyclic levels in cells.
relativityfan
Messages
75
Reaction score
0
hi,

DNA and RNA seem to be very peculiar molecular structures that are able to replicate themselves, and they are unique regarding this point, right?. But which chemical "magical" phenomena is responsible for this ability to reproduce?
 
Biology news on Phys.org
No magic, more like clever chemistry. No one phenomena, but combination of many.

http://en.wikipedia.org/wiki/Transcription_(genetics )
 
Last edited by a moderator:
the pairing of the bases by hydrogen bonds is probably the main thing
 
granpa said:
the pairing of the bases by hydrogen bonds is probably the main thing

But the pairing doesn't have much to do with replication, does it?
 
chemisttree said:
But the pairing doesn't have much to do with replication, does it?

Actually for replication, the DNA molecule needs to be split apart. This is done by helicases which break the hydrogen bonds between A-T and G-C pairs. However since A-T pairs have only 2 hydrogen bonds compared with 3 bonds in G-C pairs, they are easier to break. Therefore the splits are usually done in places rich in A-T pairs.
 
To quote the original Crick-Watson double-helix paper: "It has not escaped us that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material."
 
Interphase
 
tkpopwers said:
Interphase
interphase is when the replication of dna occurs in the cells
 
relativityfan said:
hi,

But which chemical "magical" phenomena is responsible for this ability to reproduce?

Here's the chain of events I found in Wikipedia:

"Within eukaryotes, DNA replication is controlled within the context of the cell cycle. As the cell grows and divides, it progresses through stages in the cell cycle; DNA replication occurs during the S phase (Synthesis phase). The progress of the eukaryotic cell through the cycle is controlled by cell cycle checkpoints. Progression through checkpoints is controlled through complex interactions between various proteins, including cyclins and cyclin-dependent kinases.[16]"

"Cyclins are so named because their concentration varies in a cyclical fashion during the cell cycle; they are produced or degraded as needed in order to drive the cell through the different stages of the cell cycle."

Now note the concentration of Cyclin-E in the diagram below: It reaches a maximum right about the start of S-phase so perhaps if you wanted to delve further, you could investigate what mechanism controls the cyclic concentration of cyclin molecules in the cells?
 

Attachments

  • cell cycle.jpg
    cell cycle.jpg
    18.8 KB · Views: 594
Back
Top