Both starch and cellulose are made of glucose, one of the main sources of energy for the human body. Yet... we can digest starch that we find in things like potatoes or flour, but we cannot digest cellulose, a compound that is found in virtually every plant... Why?!?
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Sources
Chemistry of glucose linkages
· https://en.wikipedia.org/wiki/Glycosidic_bond
· https://en.wikipedia.org/wiki/Anomer
· https://en.wikipedia.org/wiki/Polysaccharide
Glycogen & Starch metabolism
· https://findanyanswer.com/can-glycogen-be-digested-by-humans
· Biochemistryby J. M. Berg et al. 9th Ed. 2019 ISBN 978-1-319-11465-7; p. 679ff
· https://en.wikipedia.org/wiki/Starch
· https://en.wikipedia.org/wiki/Glycogen
· https://en.wikipedia.org/wiki/Glycogenolysis
Cellulose digestion
· https://en.wikipedia.org/wiki/Ruminant#Digestive_system_of_ruminants
· https://en.wikipedia.org/wiki/Rumen
· https://en.wikipedia.org/wiki/Cellulose
· https://en.wikipedia.org/wiki/Cellulase
· https://en.wikipedia.org/wiki/Hindgut_fermentation