According to the Bergonie-Tribondeau law, which type of cells are the most radiosensitive?

The Bergonie-Tribondeau law states that the radiosensitivity of cells is directly proportional to their reproductive activity and inversely proportional to their degree of differentiation. This means that cells that are rapidly dividing and are less specialized tend to be more sensitive to radiation.

Embryonic tissue cells are in a stage of rapid division and are not yet fully differentiated, making them highly radiosensitive. This high sensitivity is critical during developmental phases when tissues are forming and rapidly growing. As cells differentiate and become specialized, their sensitivity to damage from radiation decreases.

In contrast, nerve cells and muscle cells are highly specialized and have low mitotic activity, which makes them more resistant to radiation damage. Skin cells, while more radiosensitive than nerve or muscle cells, do not reach the level of sensitivity exhibited by embryonic cells, as they are partially differentiated and undergo a slower turnover.

Thus, the reason embryonic tissue cells are identified as the most radiosensitive according to the Bergonie-Tribondeau law is due to their high proliferation rate and low level of differentiation during critical stages of development.