Introduction to carbohydrates

Question 1

What are the 3 types of carbs

Answer 1

Monosaccharides, disaccharides and polysaccharides

Question 2

What are monosaccharides

Answer 2

They consist of 3-6 carbons typically, a carbonyl group and several hydroxyl groups

Question 3

What are aldoses

Answer 3

They are monos with an aldehyde group

Question 4

What are ketoses

Answer 4

They are monos with a ketone group

Question 5

What is a fischer projection

Answer 5

It is used to represent carbs, places the most oxidised group at the top and shows chiral carbons as the intersection of vertical and horizontal lines

Question 6

Explain L or D isomers

Answer 6

In a fischer projection, the OH group on the chiral carbon farthest from the carbonyl group determines an L or D isomer. Left is assigned L for the L-form. Right is assigned D for the D-form

Question 7

What is D-glucose

Answer 7

It is an aldohexose with the formula C6H1206. Known as blood sugar in the body

Question 8

What is galactosemia

Answer 8

Lack of enzyme required for galactose metabolism can result in accumulation of galactose intermediates. This can have toxic effects

Question 9

How would you test for sugar

Answer 9

For reducing sugars, use fehlings as it has Cu++ so will reduce it. All monos are reducing sugars

Question 10

What is lactose

Answer 10

It is a disaccharide of beta D-glucose and alpha or beta D-glucose