Which organs are the least sensitive to radiation induced biological damage?

The nerves and brain are considered the least sensitive to radiation-induced biological damage compared to other organs listed. This is primarily due to the characteristics of the cells present in these tissues. Neurons and glial cells in the brain are generally post-mitotic, meaning they do not divide frequently. Radiation tends to cause more significant damage to rapidly dividing cells, such as those found in the skin, eyes, and thyroid.

In contrast, the skin has a high turnover rate with its epidermal cells continuously regenerating. The eyes, particularly the lens, are also sensitive to radiation because of the potential for cataract formation due to damage to the rapidly dividing lens epithelial cells. The thyroid gland is sensitive because it actively absorbs iodine and can be affected by radiation, leading to conditions such as thyroid cancer.

Understanding the differential sensitivity to radiation helps in making informed decisions about exposure limits and protective measures in dental practices and other medical settings.