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Related Subjects: |DNA and RNA short notes |DNA replication |DNA structure in Nucleus |Mitosis and Meiosis |Cell Cycle
DNA (deoxyribonucleic acid) is the hereditary material in almost all living organisms. In eukaryotic cells, DNA is housed within the nucleus. The structure of DNA in the cell nucleus is highly organized, allowing it to fit within the confined space while remaining accessible for replication, transcription, and repair.
DNA is composed of two long strands that coil around each other to form a double helix. Each strand consists of a backbone made of alternating sugar (deoxyribose) and phosphate groups, with nitrogenous bases attached to the sugar molecules.
In the cell nucleus, DNA is packaged into chromatin to fit within the limited space and to regulate gene expression. Chromatin is composed of DNA, histone proteins, and non-histone proteins.
During cell division, chromatin condenses to form chromosomes, ensuring the accurate segregation of DNA to daughter cells. Each chromosome contains a single, continuous DNA molecule.
The organization of DNA within the nucleus is dynamic and allows for efficient regulation of gene expression and DNA replication.
DNA in the cell nucleus is organized into a highly structured and compact form to fit within the limited space while remaining accessible for essential cellular processes. The double helix structure of DNA, wrapped around histone proteins to form nucleosomes, further condenses into chromatin fibers and chromosomes. This organization ensures efficient regulation of gene expression, DNA replication, and repair, maintaining the integrity of the genetic information crucial for the cell's function and survival.