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> In cell division the DNA must be unzipped, opened and divided accurately:
> 
> https://phys.org/news/2017-01-reveals-dna-helicase-replication-fork.html
> 
> "The latest study from long-time collaborators Huilin Li, Ph.D., and Michael O'Donnell, Ph.D., published today in the Proceedings of the National Academy of Sciences, elucidates the interaction between DNA and the eukaryotic enzyme CMG helicase, which opens the DNA double helix like the slider of a zipper and prepares the genetic code for copying.
> 
> "'Since discovery of the DNA double helix more than 50 years ago, helicase's activity in preparing DNA for replication has been poorly understood," says Li, professor at Van Andel Research Institute.
> 
> ***
> 
> "Findings from the new study reverse a long-held assumption about the orientation of helicase around DNA. Images taken during DNA unwinding demonstrate that helicase's N-tier ring leads the C-tier motor ring and makes first contact with double-stranded DNA. Such orientation is opposite from the currently accepted polarity and has important implications in understanding the mechanism of replication.
> 
> "Helicase activity has long been recognized as a critical part of DNA replication, itself a fundamental process in the propagation of life. With the publication of this study, scientists have a more complete picture of how most advanced life on Earth proliferates.
> 
> "This study involved evaluation of CMG helicase purified from the baker's yeast Saccharomyces cerevisiae, an organism commonly used to model higher eukaryotes, including humans.
> 
> "The structure of the helicase on DNA was derived at Rockefeller University's cryo-electron microscopy (cryo-EM) core facility, leveraging a groundbreaking imaging technology that has revolutionized scientists' ability to visualize and understand the role of fundamental biological processes."
> 
> Comment: Here we see a giant molecule, an enzyme, following information/instructions to accurately divide DNA so two new cells ca form. Knowledge of the amazing complexity grows. Not by chance. Had to be part of the initial cells. Had to be a mechanism present in the first existing cells or life could not continue by cell division, as it did with the earliest bacteria. In other words life appeared with a mechanism to continue from the beginning.