Final answer:
DNA replication is vital for the growth and development of a multi-cellular organism because it ensures that new cells receive a complete set of genetic information, allowing for the maintenance of genetic fidelity during cell division, and supports genetic variation for evolution.
Step-by-step explanation:
DNA replication is crucial for the growth and development of a multi-cellular organism because it allows for the production of new cells during cell division (mitosis). This process ensures that each new cell receives a complete set of genetic information, preserving the organism's genetic continuity. Furthermore, DNA replication facilitates genetic variation and evolution through processes such as meiosis and sexual reproduction, which can introduce new genetic combinations. If DNA replication did not occur, or was incomplete prior to cell division, it could result in cells with missing or inadequate genetic information, leading to malfunction or disease.
When a cell divides, each new (daughter) cell must have an exact copy of the DNA from the parent cell. This is accomplished through DNA replication, where enzymes create a complementary strand for each original strand of DNA, ensuring the new cells are genetically identical to the parent cell. The genetic information encoded within DNA includes the instructions necessary for protein synthesis, which in turn determines the structure and function of the cell, influencing the organism's traits and characteristics.
All in all, DNA replication is essential for the maintenance of genetic fidelity during cell division, supporting the organism's growth, development, and ability to reproduce.