Carbohydrates

Question 1

3 common monosaccharides

Answer 1

Glucose
Galactose
Fructose

Question 2

What is a monosaccharides

Answer 2

The monomer from which larger carbohydrates are made

Question 3

What does the condensation reaction between two monosaccharides form which bond

Answer 3

A glycosidic bond

Question 4

What two monosaccharides condense to form maltose

Answer 4

Two glucose molecules

Question 5

3 different disaccharides

Answer 5

Maltose
Sucrose
Lactose

Question 6

What two monosaccharides condense to form sucrose

Answer 6

Glucose molecules + fructose molecule

Question 7

What two monosaccharides condense to form lactose

Answer 7

Glucose molecule + galactose molecule

Question 8

How many isomers does glucose have
What are they called

Answer 8

2
Alpha and beta

Question 9

How are polysaccharides formed

Answer 9

The condensation of many glucose units

Question 10

How are glycogen and starch formed

Answer 10

The condensation of a-glucose

Question 11

How is cellulose formed

Answer 11

The condensation of b-glucose

Question 12

Formula glucose

Answer 12

C6H12O6

Question 13

What are sugars with 6 carbon atoms called

Answer 13

Hexose sugars

Question 14

What are single sugar molecules called

Answer 14

Monosaccharides

Question 15

Key feature of monosaccharides with water + why

Answer 15

They are soluble in water

Large number OH groups ( hydroxyl group) these can form hydrogen bonds with water molecules so are soluable

Question 16

What does hydrophilic means + what this mean the molecule does

Answer 16

Water loving
All hydrophilic molecules dissolve in water

Question 17

What is a pentose monosaccharide

Answer 17

Contains 5 carbor atoms

Question 18

Example of a pentose monosaccharide

Answer 18

Ribose

Question 19

What type of monosaccharide is glucose

Answer 19

Hexose monosaccharide

Question 20

How to tell difference between a-glucose and b- glucose

Answer 20

If the hydroxyl group (OH) is above H the it is b-glucose
If the hydroxyl group (OH) is below H the it is a-glucose

Question 21

How do disaccharides form

Answer 21

When two monosaccharides chemically react together

Question 22

a-glucose + a-glucose =

Answer 22

Maltose

Question 23

What do we also produce when we make a disaccharides + how

Answer 23

Water
Hydrogen atom + hydroxyl atom

Question 24

What happens during a hydrolysis reaction (to do with saccarides)

Answer 24

Water is added to the disaccharides
To break glycosidic bond
convert it back into two monosaccharides

Question 25

How many and which side flips from alpha to beta

Answer 25

Right hand side OH above BUT ONLY ON 1 SIDE

Question 26

Test for reducing sugar

Answer 26

Heat Benedict sample in water bath to 50 degrees
Stays blue - negative
Brick red - positive.

Question 27

Test for non-reducing sugar

Answer 27

Performed test for reducing sugar.
If negative ….
Heat new sample in dilute hydrochloric acid
Neutralise by adding sodium hydrogen carbonate
Heat sample with Benedict’s
Same policy
Stays blue- negative
Brick-red - positive

Question 28

Test for starch

Answer 28

Add iodine SOLUTION
Negative - stays orange/brown
Positive - blue- black