Chemotherapy Biotherapy Certification ONS Practice Testq

In which phase do cancer cells complete the cell cycle more quickly by reducing the duration?

1. High growth fraction

2. Low growth fraction

3. Resting phase

4. Metaphase

The correct answer is: High growth fraction

Cancer cells often exhibit a high growth fraction, which refers to the proportion of cells that are actively dividing compared to those that are resting. When cancer cells have a high growth fraction, they progress through the cell cycle at an accelerated rate. This is typically due to alterations in regulatory mechanisms that usually control the timing and duration of cell cycle phases. By shortening the time spent in each phase (particularly the G1 phase), these rapidly dividing cancer cells can proliferate quickly, leading to tumor growth. In this context, other phases or states, such as low growth fraction, resting phase, or metaphase, do not present the same characteristics. Low growth fraction indicates a higher number of cells that are not actively dividing, which does not support quick proliferation. The resting phase, or G0 phase, is a state of quiescence where cells are not actively preparing to divide. Metaphase, although part of the active cell cycle where chromosomes align for separation, is just one specific moment in the overall process and does not represent the overall accelerated division seen in a high growth fraction. Thus, the high growth fraction accurately captures the phenomenon of cancer cells completing the cell cycle more quickly.