Eukaryotic Chromosomes
نویسنده
چکیده
The eukaryotic genome is made up of DNA/protein complexes called chromosomes. Despite the compaction of the DNA (deoxyribonucleic acid) with proteins, gene sequences embedded within chromosomes must still be available for transcription by RNA (ribonucleic acid) polymerases and all of the DNA must be capable of being copied by DNA polymerases. Chromosomes have two main functions: to ensure that the DNA is segregated equally to daughter nuclei at cell division, and to ensure that the integrity of the genome is maintained and accurately replicated in each cell cycle. The elements responsible for these functions are centromeres, telomeres and replication origins, respectively (Figure 1).
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