DNA circles go into our chromosomes. Conventional theory states that they when they enter, they fuse with the main chromosome and become a linear segment of it. DNA circles also come out of our chromosomes. Conventional theory says this means they have to reform circles prior to exiting the chromosome. The second law of thermodynamics makes the likelihood of regenerating a circle from a fused linear segment more improbable as the size of the DNA circle increases. A quick google search indicates that a broken chromosome from a bacterium like E. coli has a linear length of about 1,200 microns, similar to lengths found in double minute circular chromosomes released from chromosomes like our own when they are damaged by radiation or drugs. Our own cells are in the range of 10 microns in diameter, so a linear chromosome that is 120 times the length of the cell must somehow join together at a single junction point within the cell in the presence of more than 500 times as much other nuclear DNA to form a circular chromosome. When you really think about it, how can this make any sense? Isn’t it more probable that the circular chromosome pre-existed in the main chromosome and was simple plucked away from an attachment site like a cassette from a tape recorder or a memory chip from a computer?
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