Final answer:
Cells do wear out over time and need to be replaced. The body's ability to fix DNA mistakes decreases with age. Cell division and replacement play a vital role in maintaining the body's functions and repair.
Step-by-step explanation:
Cells do wear out over time and need to be replaced. As cells age, they may not function as efficiently and can lead to diseases associated with aging. The body's ability to fix mistakes in its DNA also decreases with age, which can affect DNA replication. However, the process of cell division and replacement helps to maintain the body's functions and repair itself.