How does salivary amylase work

The chyme is gradually expelled into the upper part of the small intestine. Upon entry of the chyme into the small intestine, the pancreas releases pancreatic juice through a duct. This pancreatic juice contains the enzyme, pancreatic amylase, which starts again the breakdown of dextrins into shorter and shorter carbohydrate chains. Additionally, enzymes are secreted by the intestinal cells that line the villi.

These enzymes, known collectively as disaccharidase, are sucrase, maltase, and lactase. Sucrase breaks sucrose into glucose and fructose molecules. Maltase breaks the bond between the two glucose units of maltose, and lactase breaks the bond between galactose and glucose. Once carbohydrates are chemically broken down into single sugar units they are then transported into the inside of intestinal cells.

When people do not have enough of the enzyme lactase, lactose is not sufficiently broken down resulting in a condition called lactose intolerance. The undigested lactose moves to the large intestine where bacteria are able to digest it. The bacterial digestion of lactose produces gases leading to symptoms of diarrhea, bloating, and abdominal cramps.

Lactose intolerance usually occurs in adults and is associated with race. The severity of the symptoms depends on how much lactose is consumed and the degree of lactase deficiency. The cells in the small intestine have membranes that contain many transport proteins in order to get the monosaccharides and other nutrients into the blood where they can be distributed to the rest of the body.

The first organ to receive glucose, fructose, and galactose is the liver. The liver takes them up and converts galactose to glucose, breaks fructose into even smaller carbon-containing units, and either stores glucose as glycogen or exports it back to the blood. How much glucose the liver exports to the blood is under hormonal control and you will soon discover that even the glucose itself regulates its concentrations in the blood.

Glucose levels in the blood are tightly controlled, as having either too much or too little glucose in the blood can have health consequences.

Glucose regulates its levels in the blood via a process called negative feedback. An everyday example of negative feedback is in your oven because it contains a thermostat. The glucose thermostat is located within the cells of the pancreas. After eating a meal containing carbohydrates glucose levels rise in the blood.

Different enzymes Enzymes can break down nutrients into small, soluble molecules that can be absorbed. Where enzymes are produced Enzyme Substrate End-products Where produced Salivary amylase Starch Maltose Salivary glands Protease Protein Amino acids Stomach, pancreas Lipase Lipids fats and oils Fatty acids and glycerol Pancreas Pancreatic amylase Starch Maltose Pancreas Maltase Maltose Glucose Small intestine Where digestion happens Proteases catalyse the breakdown of proteins into amino acids in the stomach and small intestine Lipases catalyse the breakdown of fats and oils into fatty acids and glycerol in the small intestine Amylase catalyses the breakdown of starch into maltose in the mouth and small intestine Maltase catalyses the breakdown of maltose into glucose in the small intestine.

Salivary amylase. Salivary glands. Starch keeps on giving blue colour with iodine till it is completely digested into maltose. At this point, no blue colour is formed. This is the end point or achromic point. Cite this Simulator:. Action of Salivary Amylase on Starch. Cite this Simulator: amrita. Retrieved 15 November , from amrita. Regina Bailey. Biology Expert. Regina Bailey is a board-certified registered nurse, science writer and educator. Updated February 26, Major Enzymes in Saliva Salivary amylase also known as ptyalin breaks down starches into smaller, simpler sugars.

Salivary kallikrein helps produce a vasodilator to dilate blood vessels. Lingual lipase helps to break down triglycerides into fatty acids and glycerides. Featured Video. Cite this Article Format. Bailey, Regina. Salivary Amylase and Other Enzymes in Saliva. Nutrient Absorption in the Digestive System. Hypothalamus Activity and Hormone Production. Epithelial Tissue: Function and Cell Types.

Carbohydrates: Sugar and Its Derivatives.