-
Use Smooth (Small Intestine)
The small intestine is a tube that lies between the stomach and large intestine, 2.5 cm in diameter and 3-5 m long. The small intestine consists of three parts, namely the duodenum (duodenum, 25-30 cm long), the empty intestine (jejunum, 1-1.5 m long) and the absorptive intestine (ileum, 2-2.5 m long). The structure of the small intestine has many intestinal protrusions (villus = singular, villi = plural), which functions to expand the absorption surface, so that food can be completely absorbed. Each protrusion of the intestine contains a net of capillaries and lymph vessels (lacteal). In the duodenum there are ducts from the pancreas and bile. In the small intestine, peristaltic movements occur from rhythmic contractions of longitudinal and circular smooth muscles that move chyme (intestinal pulp) downward along the tract. The intestine functions to digest food chemically with enzymes derived from the intestinal glands, pancreas and bile produced by the liver.

Types of absorption in the small intestine, namely:
- Carbohydrate absorption
- Glucose absorption occurs simultaneously with the active transport of sodium ions (contransport).
- Fructose is transported via facilitated diffusion
- Other monosaccharides can be absorbed by simple diffusion.
- Protein absorption
Amino acids enter the cells of the small intestine through active transport.
- Fat absorption
Fatty acids and glycerol enter the body of intestinal cells by diffusion. Small fatty acid molecules (short carbon chains) move into the villous capillaries, while large fatty acid molecules (long chains) and glycerol will form chylomicrons into the lacteals to the lymph system and systemic circulation.
- Absorption of water, electrolytes and vitamins
- Water is absorbed passively by osmosis
- Water soluble vitamins (C and B) are absorbed by diffusion. Fat soluble vitamins (A, D, E, K) are absorbed with fat.
- Calcium absorption according to food intake and body needs is regulated by parathyroid hormone and vitamin D. Iron is bound by globulins.
-
Large Intestine (Colon)
The large intestine does not have a protrusion of the intestine, but has considerable stretchability. The large intestine consists of the following parts:
- cecum, is a closed pouch and has a vermiform appendix (appendix).
- column, It is divided into ascending (ascending) colon, transverse (transverse) colon, descending (descending) colon and S-shaped sigmoid colon.
- anal, Has a length of 12-13 cm, composed of the anal canal mucosa in the form of ventricular folds containing arteries and veins, smooth muscle anal sphincter and skeletal muscle anal sphincter that surrounds the anus.

The functions of the large intestine are:
- Absorbs 80%-90% of water and electrolytes from the remaining chyme so that the chyme becomes semi-solid
- Produces mucus that does not contain enzymes
- Is a place for bacteria that are able to digest a little cellulose and produce few calories, and produce vitamin K, riboflavin, thiamine and gas
- Removing waste in the form of feces (brown color comes from bile pigments, odor comes from the work of bacteria).
Thank you, I hope this article is useful.
Also read: The Complete Explanation of the Pancreas, Liver and Bile
http://dosenbiologi.co.id/pencepatan-pankr…mpedu-tercomplete/
Source : sel.co.id