Digestion of Carbs, etc.pdf - Mrs Stovel

OTHER THINGS TONOTE:
• E. coli bacteria living in the LI help breakdown and soften waste material
• E. coli also produce vitamin B and K from fibre (cellulose)
• Fibre is not a nutrient due to the fact that we do not possess the enzymes that are necessary for
its digestion.
Fibre is however, considered to be a very important component in our diet. Fibre acts like a
sponge in the LI, allowing the feces to hold on to some water and thus allow it to stay soft
(prevents constipation). Fibre also serves as a "scrub brush" to clean the intestines as its rough
surfaces pass along the lining of the intestines. This is thought to help prevent cancer. Also,
fibre adds bulk to the waste material both by its own presence and by the fact that it holds on
to water. This added bulk serves to raise the level of peristalsis that occurs in the intestines
and to "speed up" the conveyor belt. This means that materials can be moved to the site of
removal quicker and this is also thought to have a roll both in the prevention of constipation
and in the prevention of cancer.
• Exlax is a laxative. Laxatives are chemicals/drugs which increase the rate of peristalsis.
Increased peristaltic action means that materials pass through the digestive tract at a faster rate.
The faster rate prevents both digestion and absorption of both food and water from occurring
at their normal rates. As a result, the feces pass through the system in approximately the same
liquid state as chyme.
• Other chemicals/drugs can also affect the digestive process, as can environmental influences
such as stress, infections (flu viruses), and the quality of food and water (free from poisons or
pathogens).