DNA wrapping
In this animation we can see the remarkable way our DNA is tightly packed up so that 6 feet long molecule can fit into microscopic nucleus of every cell. The process starts when DNA is wrapped around special protein molecules called histones.the-combined loop of DNA and protein is called a nucleosome. Next the nucleosomes are packaged into a thread the end result a fiber known as chromatin. This fiber is looped and coiled yet again. Leading finally in familiar shapes known as chromosomes. Which can be seen in nucleus of dividing cells. Chromosomes are not always present; they form around the time cell divides, when two copies of the cell DNA need to be separated,
Using computer animation based on molecular research, we are now able to see how DNA is actually copied in the living cells, you are looking at assembly line of amazing miniature biochemical machine that pull apart the DNA double helix and cranking out a copy of each strand, DNA to be copied enters production line from the bottom left, the rolling blue molecular machine is called helicase. It spins the DNA as fast as a jet engine has its unwinds the Double helix into two strands, One strand is copied continuously and can be seen spooling of toward the right. The things are not so simple to the other strand. because it must be copied backwards It is drawn on repeat in loops and copied one section at a time the end result is two new DNA molecules
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