How does irradiation attack the immune system?

How does irradiation attack the immune system?

• A. It suppresses cell division.
• B. It kills B cells and T cells.
• C. It inhibits hemoglobin formation.
• D. It destroys the thyroid.

Answer: (A)

Ionizing irradiation impairs the immune system by stopping the cells from dividing. The immune response relies on rapid replication of lymphocytes to produce enough B cells and T cells to fight pathogens, so when DNA is damaged by radiation, mitosis is hindered and lymphocyte proliferation drops. This leads to immunosuppression because there are fewer immune cells available to respond to infections. Radiation can also kill some rapidly dividing immune cells, but the most direct and consistent effect is the suppression of cell division. In contrast, inhibiting hemoglobin formation or destroying the thyroid are not primary ways irradiation targets immunity.

Ionizing irradiation impairs the immune system by stopping the cells from dividing. The immune response relies on rapid replication of lymphocytes to produce enough B cells and T cells to fight pathogens, so when DNA is damaged by radiation, mitosis is hindered and lymphocyte proliferation drops. This leads to immunosuppression because there are fewer immune cells available to respond to infections. Radiation can also kill some rapidly dividing immune cells, but the most direct and consistent effect is the suppression of cell division. In contrast, inhibiting hemoglobin formation or destroying the thyroid are not primary ways irradiation targets immunity.