Mechanical digestion involves physically breaking the food into smaller pieces. Mechanical digestion begins in the mouth as the food is chewed. Chemical digestion involves breaking down the food into simpler nutrients that can be used by the cells.
All carbohydrates are broken down into simple sugars, which are absorbed into the bloodstream. As the sugar level rises, the pancreas releases the hormone insulin, which is needed to move sugar from the blood into the cells, where the sugar can be used as energy
The glucose from glycogen is readily mobilized and is therefore a good source of energy for sudden, strenuous activity. Unlike fatty acids, the released glucose can provide energy in the absence of oxygen and can thus supply energy for anaerobic activity. The two major sites of glycogen storage are the liver and skeletal muscle.
Pepsin, an enzyme secreted by the stomach, breaks the strands down further. Trypsin, another enzyme, splits the protein strands into molecules containing one, two or three amino acids in the small intestine. Nearly all the protein in foods is digested, with the remainder passing through the large intestine. Saving Fats for Last
The food that is digested is absorbed into the blood vessels in the walls of the intestine. The finger-like projections known as villi, drastically increase the surface area of the small intestine for greater absorption of the digested food. The blood carries the absorbed food material to different parts of the body.
YAN LANG PO EH
