Which type of cells are considered the most radiosensitive?

• A. Muscle cells
• B. Rapidly dividing cells
• C. Neurons
• D. Cardiac cells

Answer: (B)

Rapidly dividing cells are considered the most radiosensitive due to their high rate of proliferation and metabolic activity. These cells, such as those found in bone marrow, the gastrointestinal tract, and skin, are more vulnerable to the effects of ionizing radiation primarily because they are in the process of dividing and synthesizing DNA. During cell division, the DNA is more susceptible to damage caused by radiation, resulting in a higher likelihood of cell death or malfunction.

In contrast, other types of cells such as muscle cells, neurons, and cardiac cells do not divide as frequently. Therefore, they exhibit greater resistance to radiation damage. Muscle cells and cardiac cells are long-lived and do not undergo rapid turnover, making them less sensitive to the effects of radiation. Neurons are also considered to be some of the most radioresistant cells in the body because they generally do not divide after reaching maturity. This decreased sensitivity to radiation exposure is vital in understanding the potential impact of radiation in both medical settings and therapeutic scenarios.