DNA packaging. Each chromosome consists of one continuous thread-like molecule of DNA coiled tightly around proteins, and contains a portion of the 6,400,000,000 basepairs (DNA building blocks) that make up your DNA. The way DNA is packaged into chromatin is a factor in how protein production is controlled. Originally created for DNA Interactive ( ). TRANSCRIPT: In this animation we'll see the remarkable way our DNA is tightly packed up so that six feet of this long molecule fits into the 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, which is sometimes described as “beads on a string“. The end result is a fiber known as chromatin. Now the chromatin fiber is coiled into a structure called a “solenoid“. This fiber is then looped and coiled yet again, leading finally to the familiar shapes known as chromos
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