What causes knots and stress when untwisting ropes?

In summary, topoisomerases are enzymes that help relieve the strain on DNA by untwisting the double helix ahead of the replication fork. This is comparable to untwisting two ropes twisted around each other, which creates supercoils and tension. However, it is unclear why this occurs only with coiled strands of rope and further research is needed to find a solution or explanation. It is possible that combing the individual strands of the rope may prevent this from happening.
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Aurelius120
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[Mentor Note -- thread moved from the schoolwork forums to GD as it seems like a more general question]

Homework Statement:: Topoisomerases help in relieving strain in the DNA ahead of the replication fork caused by the untwisting of the double helix (Topoisomerases are enzymes that participate in the over winding or underwinding of DNA).
The strain is same as caused when two ropes twisted around each other are untwisted from both ends.
Relevant Equations:: NA

1657953450285.png



As shown in the image the ropes develop supercoils on being unwound.
The knots caused due to untwisting develops tension enough to make it impossible to uncoil the rope further.

My question is :

What causes such unwanted stress(called torisonal stress maybe) and these knots?
Why does it happen only with coiled strands of rope?

All research has failed at providing the right solution to this problem(or even an incentive)
 
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I would guess that in untwisting the rope you are adding twist to the individual strands. I bet it doesn't happen if you comb it, i.e. allow the individual strands to twist freely.

It looks to me like the original twist in the rope is in the opposite direction from the larger twist shown.
 

FAQ: What causes knots and stress when untwisting ropes?

How does unwinding strands of rope affect its strength?

Unwinding strands of rope can weaken its strength because it disrupts the natural arrangement of the fibers. When strands are unwound, the rope becomes more susceptible to breaking under tension.

Can unwinding strands of rope cause tangling or knotting?

Yes, unwinding strands of rope can cause tangling or knotting if not done carefully. The individual fibers can become entangled and create knots, making it difficult to use the rope properly.

Is there a specific technique for unwinding strands of rope?

Yes, there are different techniques for unwinding strands of rope depending on the type of rope and its intended use. Generally, it is recommended to unwind the rope in a controlled and organized manner to prevent tangling and maintain its strength.

Can unwinding strands of rope be reversed?

Yes, it is possible to reverse the process of unwinding strands of rope. However, it may require special tools or techniques depending on the type of rope and the extent of the unwinding.

Does the material of the rope affect the ease of unwinding strands?

Yes, the material of the rope can affect the ease of unwinding strands. Some materials, such as natural fibers, may be more prone to tangling and knotting while others, like synthetic fibers, may be easier to unwind. It is important to consider the material when unwinding strands of rope.

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