The DNA sequence is passed on from one cell to other cells during reproduction, which may take place through mitosis (asexual reproduction) or meiosis (sexual reproduction). In simplest terms, chromosomes containing the DNA is replicated, the copies of DNA molecules are segregated and cytoplasm opens up leading to division of cell. In Meiosis, each parent cell donate half the chromosomes, while in mitosis, the cell divides into its exact copy (containing the exact DNA). In mitosis, chromosomes are copied through the different mitotic phases and the cell ends up with two copies of chromosomes, right before its division. During this copying of chromosomes, the double stranded DNA molecule dissociates into individual strands and new bases are added to to each strand to yield two separate double-stranded DNA molecules. A separate nuclear membrane is formed around each set of chromosomes and the cytoplasm divides yielding two identical cells.
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