Carbohydrates

Question 1

Monomer

Answer 1

single-molecule; small chemical unit that makes up a polymer by forming bonds

Question 2

Polymer

Answer 2

A long chain of monomers chemically bonded together.

Question 3

3 Examples of monomers

Answer 3

• amino acids
• monosaccharides
• nucleotides

Question 4

3 Examples of polymers

Answer 4

1. Carbohydrates
2. Proteins
3. Nucleic Acids

Question 5

Condensation reaction

Answer 5

A reaction in which 2 monomers become chemically bonded to each other to form a polymer through the loss of a water molecule

Question 6

Hydrolysis reaction

Answer 6

The addition of a water molecule to break down a polymer into monomers by breaking a chemical bond

Question 7

All carbohydrates contain

Answer 7

carbon, hydrogen, oxygen

Question 8

Carbohydrates general formula

Answer 8

(CH2O)n

Question 9

The 3 important monosaccharides

Answer 9

glucose, fructose, galactose

Question 10

Isomer

Answer 10

compounds with the same chemical formula but different structures

Question 11

Alpha and Beta glucose

Answer 11

H and OH swapped on Carbon 1.

Question 12

Maltose equation

Answer 12

alpha glucose + alpha glucose

Question 13

Sucrose equation

Answer 13

glucose + fructose

Question 14

Lactose equation

Answer 14

glucose + galactose

Question 15

Test for reducing sugars

Answer 15

Benedict’s test.

Add 2cm cubed of test solution.

Add to your solution, an equal amount of Benedict’s solution,

Heat in a water bath and if reducing sugars are present the benedicts will turn brick red.

Question 16

Test for non-reducing sugars

Answer 16

If negative (stays blue), hydrolyse the substance with HCl

Boil

Neutralise with NaOH

Add Benedict’s

Brick red precipitate indicates non-reducing sugar.

Question 17

Polysaccharides

Answer 17

Polysaccharides are formed when more than two monosaccharides are joined together by condensation reactions and glycosidic bonds.

Question 18

Why is starch used as an energy molecule?

Answer 18

Starch is insoluble so it doesn’t affect the water potential.
Starch can be compact so it can be stored in a small volume.

Question 19

What type of bond between monomers does starch have?

Answer 19

1-4 glycosidic bonds in amylose

1-4 and 1-6 in amylopection

Question 20

What type of bonds between monomers does cellulose have?

Answer 20

1-4 glycosidic bonds

Question 21

What type of bonds between monomers does glycogen have?

Answer 21

1-4 and 1-6 glycosidic bonds

Question 22

What monomers is starch made from?

Answer 22

Alpha Glucose

Question 23

What monomers is cellulose made from?

Answer 23

Beta glucose

Question 24

What monomers is glycogen made from?

Answer 24

Alpha glucose

Question 25

Structure of starch

Answer 25

Made of 2 polymers Amylose - Unbranched Helix Amylopecctin - A branched molecule

Question 26

Structure of cellulose

Answer 26

Polymer forms long, straight chains Chains are held in parallel by many hydrogen bonds to form fibrils

Question 27

Structure of glycogen

Answer 27

A highly branched molecule

Question 28

How does starch structure lead to function?

Answer 28

Helix can compact to fit a lot of glucose in a small space

Question 29

How does cellulose structure lead to function?

Answer 29

Many hydrogen bonds provide collective strength Insoluble - Wont affect water potential

Question 30

How does structure of glycogen lead to function?

Answer 30

Branched structure increases surface area for rapid hydrolysis back to glucose Insoluble - Wont affect water potential

Question 31

Name the 4 colours benedicts reagent displays with increasing concentrations of reducing sugars.

Answer 31

Blue Green Orange Brick Red

Question 32

Before testing with benedicts reagent what must be done to sample suspected of being a non reducing sugar?

Answer 32

BOIL with HCl then add NAOH to neautralise

Question 33

When testing for reducing sugars what temperature should the experiment be carried out at?

Answer 33

100 degrees celcius

Question 34

What is the test for a plant storage polysaccharide?

Answer 34

Test for starch Add iodine dissolved in potassium iodide Blue/Black - starch present

Question 35

What feature of polysaccharides makes them most suitable as a storage molecule?

Answer 35

Too large - Cannot leave the cell Coiled/Helical - Compact Insoluble - No osmotic effect

Question 36

What are microfibrils?

Answer 36

Small components in cell walls with long chains of monomers held in parallel by hydrogen bonds to provide strength in cell wall

Question 37

Where is starch located?

Answer 37

Plants

Question 38

What is starch function?

Answer 38

Energy storage

Question 39

What features help starch with energy storage?

Answer 39

Insoluble Highly branched Coiled

Question 40

Where is glycogen found?

Answer 40

Liver Muscle cells

Question 41

What is glycogen function?

Answer 41

Energy storage

Question 42

What features help glycogen with energy storage?

Answer 42

Insoluble Compact Large Highly branched

Question 43

What are the bonds in cellulose chains?

Answer 43

Hydrogen bonds

Question 44

Which features help cellulose gain strength?

Answer 44

Microfibrils Long straight unbranched chains

Question 45

What bonds are between individual beta glucose monomers in cellulose?

Answer 45

Glycosidic bonds

Question 46

What is the purpose of a 1-4 bond?

Answer 46

Linear polymer formation

Question 47

What is the purpose of a 1-6 bond?

Answer 47

Creates branched structure

Question 48

Structure of amylose?

Answer 48

Unbranched polymer

Question 49

Unique characteristic of amylose?

Answer 49

Coils into a helix

Question 50

Advantage of unique characteristic of amylose?

Answer 50

Allows compact storage in small spaces

Question 51

Structure of amylopectin?

Answer 51

Branched polymer

Question 52

Key benefit of amylopectin structure?

Answer 52

Larger surface area

Question 53

Enzymatic interaction of amylopectin?

Answer 53

More enzyme attachment points for glucose hydrolysis

Question 54

What is the significance of polysaccharides being insoluble?

Answer 54

No impact on cell water potential No effect on osmosis