Which of the following is NOT a characteristic that increases radiosensitivity according to the discussed law?

• A. Immaturity
• B. Size
• C. Rate of division
• D. Degree of specialization

Answer: (B)

Radiosensitivity, as described by the Bergonie–Tribondeau principle, depends on how actively a cell can reproduce and how differentiated it is. Immature, poorly differentiated cells with a long future of cell division are more vulnerable to radiation because their ongoing mitotic activity means many cells are in vulnerable stages of the cycle. Similarly, cells that divide rapidly are more radiosensitive for the same reason, and those with less specialization (less differentiated) retain greater proliferative potential, making them more susceptible to radiation damage. What this law does not link to radiosensitivity is the size of the cell; cell size does not determine how sensitive a cell is to radiation.