insoluble fiber

(noun)

Insoluble fiber may be metabolically inert and provide bulking or metabolically fermented in the large intestine as a prebiotic fiber.

Related Terms

Examples of insoluble fiber in the following topics:

  • Dietary Fiber

    • Insoluble fiber has bulking action, and it is not fermented.
    • Lignin, a major dietary insoluble fiber source, may alter the fate and metabolism of soluble fibers.
    • Some plants contain significant amounts of both soluble and insoluble fiber.
    • The plum's skin is a source of insoluble fiber while soluble fiber is in the pulp.
    • Table shows the functions and benefits of soluble and insoluble dietary fiber.

  • Overview of Hemostasis

    • Thrombin facilitates the conversion of a soluble plasma protein called fibrinogen into long, insoluble fibers or threads of the protein, fibrin.
    • Fibrin threads wind around the platelet plug at the damaged area of the blood vessel, forming an interlocking network of fibers and a framework for the clot.
    • This net of fibers traps and helps hold platelets, blood cells, and other molecules tight to the site of injury, functioning as the initial clot.

  • Importance of Carbohydrates

    • Carbohydrates contain soluble and insoluble elements; the insoluble part is known as fiber, which is mostly cellulose.
    • Fiber has many uses; it promotes regular bowel movement by adding bulk, and it regulates the rate of consumption of blood glucose.
    • Fiber also helps to remove excess cholesterol from the body.
    • Fiber binds and attaches to the cholesterol in the small intestine and prevents the cholesterol particles from entering the bloodstream.
    • Fiber-rich diets also have a protective role in reducing the occurrence of colon cancer.

  • Polysaccharides

    • The intact granules are insoluble in cold water, but grinding or swelling them in warm water causes them to burst.
    • Molecules of amylopectin are branched networks built from C-1 to C-4 and C-1 to C-6 glycoside links, and are essentially water insoluble.
    • Cotton, probably the most useful natural fiber, is nearly pure cellulose.
    • For fabrics the best cotton has long fibers, and short fibers or cotton dust are removed.
    • The product fiber is called viscose rayon.

  • Properties of Macromolecules

    • HDPE is insoluble in water and most organic solvents, although some swelling may occur on immersion in the latter.
    • LDPE is insoluble in water, but softens and swells on exposure to hydrocarbon solvents.
    • Pure cellulose, in the form of cotton, is a soft flexible fiber, essentially unchanged by variations in temperature ranging from -70 to 80ยบ C.
    • Cellulose fibers may be bent and twisted, but do not stretch much before breaking.
    • These molecules align themselves side by side into fibers that are stabilized by inter-chain hydrogen bonding between the three hydroxyl groups on each monomer unit.

  • Characteristics of Connective Tissue

    • Connective tissue fibers provide support.
    • Three types of fibers are found in connective tissue:
    • Elastic fibers are long, thin fibers that form branching network in the extracellular matrix.
    • Reticular fibers are short, fine collagenous fibers that can branch extensively to form a delicate network.
    • Collagen fibers are the strongest and most abundant of all the connective tissue fibers.

  • Precipitation Reactions

    • Precipitation reactions transform ions into an insoluble salt in aqueous solution.
    • Precipitation refers to a chemical reaction that occurs in aqueous solution when two ions bond together to form an insoluble salt, which is known as the precipitate.
    • A precipitation reaction can occur when two solutions containing different salts are mixed, and a cation/anion pair in the resulting combined solution forms an insoluble salt; this salt then precipitates out of solution.
    • To determine the solubility of an given salt, find the cationic component along the left-hand side, match it to the anionic component along the top, then check to see if it is S - soluble, I - insoluble, or sS - slightly soluble.

  • Solubility

    • The term "insoluble" is often applied to poorly soluble compounds.
    • In contrast, a non-polar solute such as naphthalene is insoluble in water, moderately soluble in methanol, and highly soluble in benzene.
    • Carbonates, hydroxides, sulfates, phosphates, and heavy metal salts are often insoluble.
    • The solubilities of salts formed from cations on the left and anions on the top are designated as: soluble (S), insoluble (I), or slightly soluble (sS).
    • Recognize the various ions that cause a salt to generally be soluble/insoluble in water.

  • Overview of Motor Integration

    • When a motor unit is activated, all of its fibers contract.
    • The number of muscle fibers within each unit can vary.
    • Motor units are generally recruited in order of smallest to largest (from fewest fibers to most fibers) as contraction increases.
    • These small motor units may contain only 10 fibers per motor unit.
    • These muscles may have as many as a thousand fibers in each motor unit.

  • Slow-Twitch and Fast-Twitch Muscle Fibers

    • Most muscles are made up of combinations of these fibers, although the relative number substantially varies.
    • Unlike slow-twitch fibers, fast twitch-fibers rely on anaerobic respiration (glycolysis alone) to produce two molecules of ATP per molecule of glucose.
    • As fast-twitch fibers generally do not require oxygenation, they contain fewer blood vessels and mitochondria than slow-twitch fibers and less myoglobin, resulting in a paler colour.
    • Muscles controlling eye movements contain high numbers of fast-twitch fibers (~85% fast-twitch).
    • Describe the different types of skeletal muscle fibers and their respective functions