degree of dna coiling
The degree of DNA coiling determines whether the chromosome strands are short and thick or long and thin. Between cell divisions, the DNA in chromosomes is more loosely coiled and forms long thin strands called chromatin . DNA is in this uncoiled form during the majority of the cell cycle, making the DNA available to the proteins involved in DNA replication and transcription. Before the cell divides, the chromatin coils up more tightly and form chromosomes. Only chromosomes stain clearly enough to be seen under a microscope. The word chromosome comes from the Greek word chroma color , and soma body due to its ability to be stained strongly by dyes.