|Table 1. Types of sugars — vital energy for all living things|
|Monosaccharides — single unit of sugar (“simple” sugars); highly soluble|
|Glucose||The sugar circulating in our blood.|
|Fructose||The sugar that makes fruit sweet.|
|Galactose||The sugar found in milk.|
|Critical subcomponents of DNA and RNA, essential for genetic transcription.|
|Disaccharides — two monosaccharides joined together; soluble|
(glucose + fructose + H20)
(glucose + galactose + H20)
|Another milk sugar.|
(glucose + glucose)
|Polysaccharides — long, chain-like polymers; not readily soluble|
|Starch (amylose and amylopectin)|
The energy storage molecule used by all plants, synthesized from glucose, present in all plant seeds and tubers, and in many fruits and rhizomes. The most consumed polysaccharide in the human diet.
In plants, this is synthesized to form cell walls; it is indigestible for humans due to lack of the enzyme cellulase, but provides fiber in our diets to promote wave-like digestive action called peristalsis.
This is the carbohydrate stored in muscle and liver tissue. When blood sugar levels go down, liver cells hydrolyze glycogen to release glucose into the bloodstream.
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