The genetic information of a cell is carried in its DNA (short for deoxyribonucleic acid). What do cells need to do between divisions to make sure that a full set of DNA gets passed on to each daughter cell?

Answer 1

Cells go through a process called DNA replication before dividing to ensure that a full set of DNA is passed on to each daughter cell. DNA replication occurs during the S phase (synthesis phase) of the cell cycle. Here's a simplified explanation of the process:

1. The two strands of the DNA double helix unwind and separate.
2. Enzymes called DNA helicases break the hydrogen bonds between the base pairs to unwind the DNA.
3. Each separated strand serves as a template for the synthesis of a complementary strand. DNA polymerase, an enzyme, adds new nucleotides to the template strands.
4. DNA polymerase ensures accurate base pairing, i.e., A with T and C with G, to maintain the correct genetic information.
5. The new strands are synthesized in opposite directions due to the antiparallel nature of DNA.
6. Continuous synthesis occurs along the leading strand, while the lagging strand undergoes discontinuous synthesis, forming small fragments called Okazaki fragments.
7. An enzyme called DNA ligase joins the Okazaki fragments to produce a continuous complementary strand.
8. The replication process continues until the entire DNA molecule is replicated.
9. Each daughter cell receives one copy of the replicated DNA, ensuring that both cells have a complete set of genetic information.

By replicating the DNA before cell division, cells ensure that each daughter cell receives an identical copy of the genetic material, enabling the transmission of genetic information from one generation of cells to the next.