Suppose you are a typical adult human...
starch
You eat a meal that contains rice and beans. You have ice
cream for dessert.
cream for dessert.
Rice contains a large amount of starch, and a modest amount
of cellulose.
of cellulose.
Beans contain starch, cellulose, and a large amount of “bean
sugar.”
sugar.”
Ice cream contains lactose.
What happens? Who gets to use the simple sugars, you or
your bacteria? To figure this out, follow the meal through
your digestive system:
your bacteria? To figure this out, follow the meal through
your digestive system:
cellulose
“bean sugar”
lactose
• Esophagus
• Stomach
• mixes and digests foods for which it
has the enzymes
• has this enzyme:
• Small intestine
• entrance: stomach, exit: large intestine
• absorbs only single sugars
• contains bacteria E. coli
• E. coli can absorb single sugars and
double-sugars like lactose
• E. coli digest sugar to CO2 and H2O
• E. coli have this enzyme:
