Within the intestine, epithelial cells originate from stem cells, proliferate in the crypts, and migrate up the villus in 2 to 5 days. This process replaces cells that are removed due to apoptosis or exfoliation. This rapid turnover makes the small intestine susceptible to:a. Radiation damage
The high cellular turnover rate of enterocytes makes the small intestine susceptible to damage by inhibitors of proliferation such as radiation and cytotoxic chemotherapy.