Weegy: is an organized structure of DNA and protein found in cells. It is a single piece of coiled DNA containing many genes, regulatory elements and other nucleotide sequences. [ Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions.
Diagram of a replicated and condensed metaphase eukaryotic chromosome. (1) Chromatid ? one of the two identical parts of the chromosome after S phase. (2) Centromere ? the point where the two chromatids touch, and where the microtubules attach. (3) Short arm. (4) Long foot.
Chromosomes vary widely between different organisms. The DNA molecule may be circular or linear, and can be composed of 100,000 to 10,000,000,000[1] nucleotides in a long chain. Typically, eukaryotic cells (cells with nuclei) have large linear chromosomes and prokaryotic cells (cells without defined nuclei) have smaller circular chromosomes, although there are many exceptions to this rule. Also, cells may contain more than one type of chromosome; for example, mitochondria in most eukaryotes and chloroplasts in plants have their own small chromosomes. ]
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