The Digestive System
The sphincter valve located between the small intestines and the large intestines (colon) is known as the ileocecal valve.
Enzymes are proteins which make possible or facilitate a chemical reaction under a given environmental condition. Digestive enzymes are enzymes which help break down food substances into forms that can be absorbed and assimilated by the body.
The Digestive Enzymes
Digestive enzymes are very important. Unfortunately, starting at about the age of 30, the body's secretion of enzymes begins to gradually decline. By the senior years the decline is usually significant enough to adversly effect the digestion and assimilation of food. This is one reason why digestive disturbances are common in the elderly, and why seniors often have difficulty getting the nutrients they needa contributing factor to many health problems including osteoporosis, which is caused primarily by insufficient assimilation of proteins, calcium and other minerals. Most elderly people can benefit by taking food enzymes with their meals, along with a good multi-vitamin and mineral supplement.
Younger individuals commonly suffer from insufficient digestive enzymes as well. Tons of antacids are purchased each year by individuals who are suffering more from a deficiency of enzymes (and from improper chewing of their food) than from excess stomach acid. Most of these individuals would be much better served by supplementing their diets with food enzymes.
Digestive enzymes are normally secreted 1) in the mouth (as part of the saliva), 2) by the stomach, and 3) released into the small intestines from the liver and pancreas. The major enzymes are:
A note about terminology: You may have noticed that the names of many enzymes end with -ase, the suffix that is used to indicate an enzyme. The suffix that is used to indicate a sugar (or simple carbohydrate) is -ose. Thus cellulase breaks down cellulose. In the same way, lipase breaks down lipids (fats); pectinase breaks down pectin; protease breaks down proteins, etc.
- Amylase, also called ptyalin, is an enzyme that aids the breakdown of starches. It is secreted in the saliva and the pancreatic juices.
- Mycozyme is an enzyme that also digests starches.
- Lipase, secreted by the pancreas, refers to any of several enzymes that increase the breakdown of fats (lipids).
- Protease, an enzyme that helps the breakdown of protein, is also secreted by the pancreas. Enzymes that breakdown protein are known as a proteolytic enzymes.
- Pepsin is an enzyme released in the stomach that also helps with the breakdown of protein.
- Pancreatin refers to pancreatic enzymes. Pancreatin is often obtained from cows or pigs and used as a dietary supplement.
- Bile, also called gall, is a bitter, yellow-green secretion of the liver, stored in the gallbladder, and released during digestion when fats enter the first part of the small intestine (duodenum). Bile emulsifies fats preparing them for further digestion and absorption in the small intestine.
- Cellulase is an enzyme that breaks down cellulose, the carbohydrate that is the main part of the cell walls of plants. Cellulose is nondigestible by humans because we to not produce the enzyme cellulase. Cellulase is produced by grazing animals such as cows (with the aid of the beneficial bacteria that reside in the animal's digestive tract), and is the reason why they can get nutrition from plants such as grasses. The human body does not produce cellulase, however, it is sometimes included in enzyme supplements since it can help us break down the cell walls of plants better, thereby getting the most nutrition from the herbs and other plants that we eat.
Which of the following enzymes help break down fats (lipids)?
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