Digestion of Carbohydrates Flashcards
After a meal, the body receives a large amount of carbohydrates what are they used for?
To fill up energy stores in the body such as glycogen in the muscles and liver
(this phase of metabolism is orchestrated by inuslin)
Where is the glucose delivered to and for what purpose?
Delivered to the brain and erythrocytes (red blood cells) to fuel these organs and excessive amounts are converted into fat
What is the first step in the digestion of carbohydrates?
Hydrolysis of disaccharides and polysaccharides that are abundant in our nutrition
What is starch hydrolysed to and by what?
Glucose and smaller oligosaccharides by α- amylase
What is lactose hydrolysed to and by what?
By lactase to yield glucose and galactose
What is sucrose hydrolysed to and by what?
By sucrase to yield fructose and glucose
What happens with sucrase and maltase?
They are combined in one enzyme found in the brush-border of the small intestine
What can the lack of any of the enzymes involved in carbohydrate digestion cause?
Health consequences
What populations are is lactose intolerance frequent in?
Asian, African and Aboriginal population
What causes lactose intolerance?
A lack of lactase, which results in the fermentation of lactose by intestinal bacteria
- generates a large amount of fermentation products, which cause diarrhea by reverse osmosis
What is one of the most notable indigestible carbohydrates in human nutrition?
Cellulose
What are non-digestible carbohydrates (fiber) important for?
Important as nutrients for the intestinal microflora
Why is microflora important?
It ferments fiber to short-chain fatty acids such as formate, acetate, and propionate, which are important nutrients for the colon.
