Introduction to carbohydrates Flashcards
What are the three types of simple sugar?
monosaccharides
disaccharides
polysaccharides
What is a Fischer projection?
used to represent carbohydrate structure - places most oxidised carbon at the top
How is an L or D isomer identified?
the -OH group on the chiral carbon furthest from the carbonyl group determines an L or D isomer
- left is the L form and right is the D form
What is D-glucose?
the monosaccharide in polymers of starch, cellulose and glycogen
What is Galactosemia?
a lack of the enzymes required for galactose metabolism which results in an accumulation of galactose intermediates
What is glycogen?
the storage form of glucose
What is used to test for sugars and what is the colour change?
Fehling’s reagent - brown to blue in presence of glucose
How is maltose made?
glucose + glucose
How is lactose made?
glucose + galactose
How is sucrose made?
glucose + fructose
What are examples of important disaccharides?
maltose
lactose
sucrose
What are examples of important polysaccharides?
glycogen
starch
cellulose
How does a lactose intolerance occur?
lack of lactose enzyme in the small intestine causes lactose to pass into the colon and be fermented by bacteria
