During which process are cells most sensitive to radiation?

• A. Interphase
• B. Mitosis
• C. Apoptosis
• D. Meiosis

Answer: (B)

Cells are most sensitive to radiation during mitosis, which is the process of cell division. During this phase, the genetic material is condensed and organized, making the cell particularly vulnerable to damage. The DNA is replicated, and any interruptions or damage caused by radiation can lead to significant mutations, cell death, or disruptions in normal cell division. This heightened sensitivity is due to the fact that mitotic cells are actively engaged in processes that are crucial for maintaining genetic integrity, and therefore, radiation can have more pronounced effects during this critical time.

The other processes listed do not exhibit the same level of vulnerability to radiation. Interphase is a longer phase of the cell cycle where the cell grows and DNA is replicated, but it is less sensitive compared to mitosis because the DNA is in a less compacted state. Apoptosis, which is a form of programmed cell death, may occur as a response to damage but does not represent a phase where sensitivity is evaluated based on cell division. Meiosis, although it is another type of cell division, occurs in germ cells and involves different sensitivities compared to mitosis. Therefore, mitosis is the phase where cells are most susceptible to the damaging effects of radiation.