The small intestine absorbs 90% of the water from ingested food. Although the entire small intestine is involved in the absorption of water and lipids, most absorption of carbohydrates and proteins occurs in the jejunum.

What is the small intestine?

The small intestine is a component of the digestive system, measuring about 22 feet. It is located in the lower abdominal cavity beneath the stomach. The large intestine surrounds the abdominal cavity, framing its edges. The small intestine is one of the parts of a long pathway that food takes through your body, called the gastrointestinal (GI) tract. 

Listed are the functions of the small intestine:

  • systematically breaks food down
  • absorbs nutrients
  • extracts water
  • moves food along the gastrointestinal tract

There’s a lot involved in all this process so it can take up to five hours to complete.

What are the three parts of the small intestine?

The small intestine has beginning, middle, and end sections. Although there isn’t really a division between the parts, there are some variances in the traits they possess and the roles they serve.

Duodenum

Your stomach feeds nourishment into the duodenum, which is the first part of your small intestine. The chute descends quickly (about 10 inches long) in a “C” shape curve around the pancreas and connects to the rest of the coiled intestines.

Jejunum

The remaining small intestine is coiled inside the lower abdominal cavity. Its middle section is the jejunum which makes up a little less than half of this remaining length. The jejunum has a deep red color that is characterized by many blood vessels.

Ileum

The small intestine’s final and longest section is called the ileum. It is the stage when the blood supply is reduced and the small intestine’s walls start to shrink and constrict. The ileum is where food spends the greatest time absorbing nutrients and water.

How long does food stay in the small intestine?

Food goes through the stomach and small intestine within six to eight hours after eating. For further digestion, the food then enters the large intestine (colon), absorbs more water, and, finally, eliminates undigested food. Thus, food passes entirely through the colon in around 36 hours.

What percentage of alcohol is absorbed by the small intestine?

When you consume an alcoholic drink, about 20% is absorbed into the bloodstream when the drink passes through your stomach and the other 80% of the alcohol is absorbed into the bloodstream when the drink reaches the small intestine.

What is the name of the sphincter that separates the stomach from the small intestine?

A band of smooth muscle known as the pyloric valve or pyloric sphincter controls the passage of partially digested food and digestive juices from the pylorus into the duodenum. It separates the stomach and the small intestine. It allows the contents of the former to pass into the latter It also prevents partially digested food and digestive juices from re-entering the stomach.

What structural modification of the small intestine slows the movement of chyme through the lumen?

The combination of food and digestive juices is called chyme. The small intestine’s cirrhotic folds help food move more slowly so that it can be better absorbed and digested. These folds broaden the surface area and facilitate chyme mixing.

Furthermore, sodium bicarbonate neutralizes the acidic chyme coming from the stomach, protecting the small intestine from acid damage.

How long is the recovery from small intestine surgery?

If you’ve undergone surgery to remove part of your small or large intestine, you are likely to experience pain that comes and goes for the following days. You may feel like you have influenza (flu), low fever, or feel tired and nauseated. This is common and you should feel better after 1 to 2 weeks, and you will probably feel completely back to normal in 2 to 4 weeks.

Your bowel movements may not be consistent for several weeks. You may also see some blood in your stool. Each person recovers at a different pace.