Duplication of DNA

When it is time for a cell to divide, all of the 46 chromosomes must be copied exactly. This ensures that each new cell receives a complete set of chromosomes. The duplication of the chromosomes occurs when the cell is not dividing.

Duplication of DNA:

• The DNA unwinds and separates into two strands.
• Extra nucleotide bases (adenine, cytosine, guanine, and thymine) in the nucleus are connected to each of the single strands of DNA.
• Two double-helix molecules of DNA form, making a copy of the original DNA
• When the cell divides, one set of DNA goes into each new cell.