Question

How is the small intestine specialized for absorption?

Answer 1

Hint: The small intestine (also referred to as the small intestine) is the specialised tubular organ that collects nutrients from the diet between the stomach and the large intestine (also called the colon or large intestine). It is around 20-25 feet in length and is about as wide as the middle finger.

Complete answer:
There are three sections of the small intestine: the duodenum, jejunum and ileum.
The small intestine is responsible for nutrients, salt and water absorption. About nine litres of fluid enter the jejunum on average each day. About seven litres are swallowed by the small intestine, leaving only 1.5-2 litres to join the broad intestine. Serious small intestine defects are also manifested by food malabsorption and diarrhoea.
The small intestine's absorptive work is carried out by an intricate series of cells within its lining that accumulate and secrete salts and nutrients as well as water in order to preserve the natural balance of salt and water within the body. The absorptive mechanism is so effective that over 95 percent of ingested carbohydrates and proteins are consumed in a typical adult with a normal diet.
To execute particular roles, specific regions are modified. The duodenum, for example, plays an important part in coordinating how the stomach empties as well as the rate at which bile duct juices are expelled into the intestine. Even the duodenum is a major iron absorption site. Jejunum is the primary site for the absorption of vitamin folic acid and the most important site for the absorption of vitamin B12 and bile salts is the end of the ileum.

Note: The lining of the tiny intestinal mucosa is highly specialised in optimising nutrient digestion and absorption. To assist with absorption, the lining is strongly folded to form microscopic finger-like projections called villi that maximise the surface area.