the length of a DNA molecule in a typical mammalian cell is calculated to be approximately 2.2 metres.how is the packaging of this long molecule done to accomodate it within nucleus having dimensions in micrometer?
- Length of DNA double helix in typical mammalian cell is about 2.2 metres and all of that DNA packaged so tightly into chromosomes and squeezed into a tiny nucleus.
- The haploid human genome contains approximately 3 billion base pairs of DNA. All are packaged into 23 chromosomes. Except for ova and sperm all cells are diploid, with 23 pairs of chromosomes. In total 6 billion base pairs of DNA in each cell. Each cell contains about 2.2 meters of DNA .It is estimated that the human body contains about 100 trillion meters of DNA.
- Certain proteins (Histones) compact chromosomal DNA into the microscopic space of the eukaryotic nucleus. Thus, within the nucleus, histones bind with DNA very tightly and provide the energy to fold DNA.