Carbohydrates

Question 1

What are all biological molecules built from?

Answer 1

Monomers

Question 2

When two sun-units join together what is formed?

Answer 2

A dimer

Question 3

When many sub-units join together what is formed?

Answer 3

A polysaccharide

Question 4

Monosaccharides are the monomers of what?

Answer 4

Carbohydrates

Question 5

Monosaccharides are single what units?

Answer 5

Single sugar units with the general formula (CH2O)n

Question 6

What can these single sugar units be called?

Answer 6

Hexose sugars (because 6 is the most common number of carbon atoms)

Question 7

What are the three important monosaccharides?

Answer 7

Glucose, galactose and fructose

Question 8

Are monosaccharides soluble or insoluble? Why?

Answer 8

Soluble because they can form hydrogen bonds with water as they contain OH and H atoms

Question 9

What is the main sugar used by all cells in respiration?

Answer 9

Glucose

Question 10

Which polymers are made of glucose?

Answer 10

Starch and glycogen

Question 11

What happens when starch or glycogen is digested?

Answer 11

Glucose is produced which can be easily absorbed and transported in the bloodstream to cells

Question 12

What is galactose mainly in our diet as?

Answer 12

Part of the disaccharide sugar lactose

Question 13

Which -OH groups are on the opposite side to glucose?

Answer 13

The -OH groups on carbon one and four

Question 14

Where does fructose occur naturally?

Answer 14

In fruit, honey and some vegetables

Question 15

What do monosaccharides provide? Why?

Answer 15

A rapid source of energy because they are readily absorbed and require little/no change before being used in cellular respiration

Question 16

What reactions form disaccharides?

Answer 16

Condensation reactions

Question 17

What molecule is released as two sugar molecules combine in a condensation reaction?

Answer 17

A water molecule

Question 18

What bond is formed in the formation of a disaccharide?

Answer 18

A glycosidic bond

Question 19

What are the three important disaccharides?

Answer 19

Maltose, sucrose and lactose

Question 20

How are disaccharides split?

Answer 20

By hydrolysis reactions (where water is added to the glycosidic bond)

Question 21

What two monosaccharides join to make maltose?

Answer 21

Glucose and glucose

Question 22

When is maltose produced?

Answer 22

When amylase breaks down starch

Question 23

What two monosaccharides join to make sucrose?

Answer 23

Glucose and fructose

Question 24

What is the usual form in which sugar is transported around a plant?

Answer 24

Sucrose

Question 25

What two monosaccharides join to make lactose?

Answer 25

Galactose and glucose

Question 26

Which sugar is found in milk?

Answer 26

Lactose

Question 27

What are polysaccharides composed of?

Answer 27

Single sugar monomers (monosaccharides)

Question 28

What bond holds together polysaccharides?

Answer 28

Glycosidic bonds

Question 29

Are polysaccharides short or long chained structures?

Answer 29

Long chained structures

Question 30

Are polysaccharides soluble in water and sweet?

Answer 30

No, they are not very soluble in water and have a bitter taste

Question 31

What are the three main polysaccharides found in food?

Answer 31

Glycogen, cellulose and starch

Question 32

Who stores glycogen?

Answer 32

Animals

Question 33

Where is glycogen stored in humans?

Answer 33

In the liver and muscles

Question 34

Why can glycogen be rapidly hydrolysed?

Answer 34

Because it has numerous side branches, giving easy access to stored energy

Question 35

What contains cellulose and stores starch?

Answer 35

Plants

Question 36

What is Cellulose also known as?

Answer 36

Dietary fibre

Question 37

What is celluloses basic structure?

Answer 37

A straight chain

Question 38

What two polymers is starch formed of?

Answer 38

Amylose and amylopectin

Question 39

Which polymer has a straight chain of between 200-5000 molecules and contains 1,4 glycosidic bonds

Answer 39

Amylose

Question 40

What is the structure of amylopectin?

Answer 40

Amylopectin has side branches off its main chain, it also has 1,6 glycosidic bonds

Question 41

What does the position of the 1,4 glycosidic bonds cause?

Answer 41

The amylose chain to coil

Question 42

What do both glycogen and starch act as?

Answer 42

Storage molecules within cells

Question 43

Why are glycogen and starch suitable storage molecules?

Answer 43

Because the polysaccharide chains are compact with low solubility in water. This means they don't affect the concentration of water in they cytoplasm and so don't affect movement of water by osmosis