What are 4 ways the small intestine is well adapted to its function?

1. Length: The small intestine is much longer than the stomach and large intestine, which allows for more surface area for the absorption of nutrients. The average length of the small intestine in an adult human is about 20 feet.

2. Villi: The small intestine is lined with tiny, finger-like projections called villi. Villi increase the surface area of the small intestine even more, allowing for even greater absorption of nutrients.

3. Microvilli: The cells that line the villi are covered in even smaller projections called microvilli. Microvilli further increase the surface area of the small intestine, allowing for even greater absorption of nutrients.

4. Secretions: The small intestine secretes a number of enzymes and other substances that help to break down food and absorb nutrients. These secretions include:

* Pancreatic juice: Pancreatic juice is produced by the pancreas and contains enzymes that break down carbohydrates, proteins, and fats.

* Bile: Bile is produced by the liver and helps to break down fats.

* Mucus: Mucus is produced by the small intestine and helps to protect the intestinal lining from digestive enzymes.