Carbohydrates

Question 1

Monosaccharides

Answer 1

Glucose
Galactose
Fructose
Isomers - C6H12O6

Question 2

Disaccharides

Answer 2

2x Monosaccharides
Sucrose = Glucose + Fructose
Maltose = Glucose + Glucose
Lactose = Glucose + Galactose

Question 3

Polysaccharides

Answer 3

Polymers of glucose and complex sugars
Starch = Alpha Glucose
Glycogen = Alpha Glucose
Cellulose = Beta Glucose

Question 4

Condensation Reaction

Answer 4

Reaction that releases a molecule of water
Joins two molecules

Question 5

Hydrolysis Reaction

Answer 5

Reverse of Condensation
1 Water molecule splits a molecule into 2

Question 6

Testing for Reducing Sugars

Answer 6

(All Monosaccharides and Disaccharides but Sucrose)
1. Crush the food, add water, mix.
2. Add Benedicts Reagent
3. Heat to near boiling point
4. Positive = Blue -> Brick-Red

Question 7

Test for Non Reducing Sugars

Answer 7

(Sucrose)
1. Fresh sample + heat with hydrochloric acid
2. Neutralize with Sodium Hydrogen concentrate
3. Retest with Benedicts Reagent
4. Positive = Sucrose

Question 8

Starch - Amylose

Answer 8

In Plants
Alpha Glucose
Unbranched coiled structure
Hydrogen bonding
More compact (resistant to digestion)

Question 9

Starch - Amylopectin

Answer 9

In Plants
Alpha Glucose
Branched Polymer
Greater surface area (Energy gain at greater rate)

Question 10

Test for Starch

Answer 10

1. Add a few drops of Potassium Iodide
2. Positive = Yellow/Brown -> Blue/Black

Question 11

Glycogen

Answer 11

In Animals
Alpha Glucose
More branched form of Amylopectin
More compact (store more)

Question 12

Cellulose

Answer 12

In Plants
Beta Glucose
Mechanical strength + support in cell wall
Every other Glucose molecule flipped
Straight unbranched chains (Microfibers)
Lots of H bonds gives collective strength