Mitosis and cytokinesis. In eukaryotes the processes of DNA replication and cell division occur<span> at different times of the </span>cell division<span> cycle. During </span>cell division<span>, DNA condenses to form short, tightly coiled, rodlike chromosomes. Each chromosome then splits longitudinally, forming two identical chromatids.
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Cyanobacteria released OXYGEN into the atmosphere through photosynthesis