Question

A student is watching a video of cancer growth in humans. The student notices that the cells never slow down their division to grow; they only divide over and over again. What has caused this division to continue without a rest?

a) Cells are made to continue dividing and no harm will come to the organisms.
b) Once a cell gets into interphase, it continues to grow without stopping.
c) The checkpoint at the end of G1 and G2 phase is not working as they should be.
d) The cell is working normally.

Answer 1

The uncontrolled division of cells leading to cancer is due to a malfunction in the checkpoints at the end of the G1 and G2 phase of the cell cycle.

Step-by-step explanation:

The continuous division of cells without a rest period as observed in the video of cancer growth is caused due to failures in the cell cycle regulation mechanisms. Specifically, the checkpoint at the end of the G1 and G2 phase is not working correctly, allowing cells to skip these critical regulatory steps and divide uncontrollably. This unchecked cell division is a hallmark of cancer, where the regular 'stop' and 'go' signals that manage the transition from one phase of the cell cycle to the next are disrupted. These disruptions can result from various factors, including genetic mutations and environmental damage. Ultimately, the rapid and uncontrolled division of these cells can lead to the formation of tumors and serious health implications.