NO LINKS PLEASE!! The thin layer of epithelial tissue in the small intestines works somewhat like a cell membrane. How does its structure relate to its function in the digestive system?

The cell membrane acts as a barrier that protects the cell from the external environment and it regulates the movement of the particles or substances in and out of the cell. This function is similar to the inner workings of our digestive system. The epithelial tissues in the small intestines work as a physical barrier between the intestines and other body tissues. It also breaks down the food into smaller components and selectively absorbs nutrients, which the body uses in order to perform its life functions.

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