Which of the following is an example of a radioresistant cell?

The brain cell is considered an example of a radioresistant cell primarily due to its ability to withstand higher doses of radiation without significant damage compared to other cell types. This resilience can be attributed to several factors, including the limited rate of cell division in neural cells and the presence of efficient DNA repair mechanisms. Since brain cells, or neurons, do not rapidly proliferate, they are less likely to be affected by radiation, which typically targets actively dividing cells.

In contrast, the other cell types listed are more susceptible to radiation damage. White blood cells, particularly lymphocytes, are highly sensitive because they are involved in immune responses and can quickly divide. Skin cells also have higher turnover rates as they constantly regenerate to maintain the protective barrier of the skin. Similarly, gastrointestinal tract cells divide frequently due to the ongoing need for tissue renewal because of their constant exposure to various substances.

Thus, brain cells exemplify radioresistant cells due to their structural and functional characteristics that confer protection against radiation effects, while other cell types demonstrate higher sensitivity to radiation exposure.