Lactose And Lactase Reaction Diagram

Pouring milk into a bowl.

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Lactose is milk sugar--it'due south much less sugariness than table sugar, and occurs naturally in milk and other dairy products. While yous can certainly burn down the chemical components of lactose for free energy, it doesn't serve unique cellular functions--you lot tin can fire other carbohydrates instead with no sick event whatsoever.

Lactose Chemistry

Lactose is a disaccharide, meaning it'south made up of two smaller sugar units. The sugar units, chosen glucose and galactose, both serve equally sources of energy for your cells. When you consume lactose, yous break information technology into glucose and galactose using the enzyme lactase, explain Drs. Reginald Garrett and Charles Grisham in their book "Biochemistry." You lot then absorb these pocket-sized sugars into your bloodstream, and from in that location, cells take them upwardly for free energy utilize.

Combusting Sugars

The cells chemically "fire" glucose and galactose, which releases energy, in a process very similar to that through which you can burn wood in a fireplace to release energy. Using a variety of enzymes, which are chemicals that assist in cellular reactions, the cells intermission down glucose and galactose into carbon dioxide and h2o. This procedure generates a large quantity of ATP, which is a chemical free energy molecule that the cells then utilize to fuel various processes, including motility.

Special Importance

You can obtain glucose from many sources; tabular array sugar contains glucose, and starch is composed of nil but long bondage of glucose, explicate Drs. Mary Campbell and Shawn Farrell in their book "Biochemistry." As such, you don't need the glucose from lactose to fill cellular energy needs. Further, your cells can convert galactose to glucose, which they do before burning it for free energy. As such, you have no special demand of the galactose in lactose. Lactose serves as a practiced source of energy, but isn't required to maintain health.

Additional Functions

In addition to burning the components of lactose--glucose and galactose--for immediate energy, y'all tin can use them to make one of two free energy-storage molecules. Your cells tin brand glycogen from both glucose and galactose, where glycogen is a form of sugar storage used by the liver and muscles. This provides a supply of energy for periods of fasting. You can also catechumen both glucose and galactose into fatty for energy storage purposes.