Question

What could happen if cells remain in the cell cycle indefinitely?

Answer 1

After each division or replication . The cells "Telomeres", a protective sequences of DNA on the end of a chromosome that prevent degradation of the chromosomal DNA, shortens after each cell cycle.

This shortening has been correlated with negative effects such as age related diseases and shortened lifespans in humans.

This is also due to the "end-replication problem". Unlike bacterial chromosomes, the chromosomes of eukaryotes are linear , meaning that they have ends. The DNA at the very end of the chromosome cannot be fully copied in each round of cell cycle , resulting in a slow & gradual shortening of the chromosome.

Cancer cells, can undergo numerus cell cycle due to an enzyme complex called "telomerase", present in large quantities in cancerous cells,they rebuilds the telomeres through synthesis of telomeric DNA repeats, thus allowing cell division to continue indefinitely.