This sample menu for a day gives you 37 grams of fiber: 1  Breakfast: whole-grain bran flake cereal (5 grams of fiber), half a banana (1.5 grams of fiber), and skim milk. 2  Snack: 24 almonds (3.3 grams of fiber) and a quarter cup of raisins (1.5 grams of fiber)
1 large circular folds called plicae circulares (shown in the diagram to the right), most numerous in the upper part of the small intestine. 2  smaller folds called villi, which are finger like mucosal projections, about 1mm long.o aid in digestion and absorption: 1  the small intestine secretes enzymes and has mucous producing glands. 2  The pancreas and liver also deliver their exocrine secretions into the duodenum. 3  The mucosa is highly folded.
Despite its name, the small intestine is the largest part of the digestive tract. Even though the small intestine is only about one inch in diameter, the small intestine is approximately 20 to 23 feet long. Because the small intestine is long, the small intestine has a lot of surface area. This large surface area helps to ensure that the nutrients are absorbed. The small intestine has three parts called the duodenum, the jejuneum, and the ileum. As mentioned previously, the duodenum begins at the pyloric sphincter. It then wraps around the head of the pancreas and ends at a turn called the duodenojejuneal flexure. It then becomes the jejuneum.