Carbohydrates

Question 1

What’s a polymer?

Answer 1

Large, complex molecules composed of large chains of monomer s joined together.

Question 2

What’s a monomer?

Answer 2

Small, basic molecular unit.

Question 3

3 examples of monomers

Answer 3

Amino acids, monosaccharides and nucleotides

Question 4

What type of bond is formed between a two monosaccharides during a condensation reaction?

Answer 4

Glycosidic

Question 5

Glucose+glucose=?

Answer 5

Maltose

Question 6

Glucose+fructose=?

Answer 6

Sucrose

Question 7

Glucose+galactose=?

Answer 7

Lactose

Question 8

What’s sugar a general term for?

Answer 8

Monosaccharides and disaccharides.

Question 9

What’s the test for sugars called?

Answer 9

Benedict’s test

Question 10

How do you test for a reducing sugar?

Answer 10

Add Benedict’s reagent to sample and heat.
Positive=coloured precipitate.
Blue>brick red

Question 11

How do you test for a non-reducing sugar?

Answer 11

Neg for reducing sugar.
Get sample and add dilute hcl and heat.
Neutralise with sodium hydrogencarbonate.
Carry out Benedict’s test- add Benedict’s reagent and heat.
Pos= colour change, blue>brick red.

Question 12

What’s starch the main energy storage material in?

Answer 12

Plants

Question 13

How do plants store excess glucose?

Answer 13

As starch

Question 14

What does a plant do when it needs more glucose for energy?

Answer 14

Breaks down starch

Question 15

Which two polysaccharides is starch a mixture of?

Answer 15

Amylose and amylopectin

Question 16

What structure does amylose have?

Answer 16

Long, unbranched chain of alpha glucose.

Coiled shape.

Question 17

Why does amylose have a coiled structre?

Answer 17

The angles of the glycosidic bonds

Question 18

Why’s amylose good for storage?

Answer 18

Compact- due to coiled structure.

Fit more in a small space.

Question 19

What’s the structure of amylopectin?

Answer 19

Long, branched chain of alpha glucose.

Side branches.

Question 20

Why can the glucose in amylopectin be released quickly?

Answer 20

Side branches allow enzymes to break down molecule to get at glycosidic bonds easily.

Question 21

How does starch not cause water to enter cells by osmosis?

Answer 21

Insoluable in water
Doesn’t affect water potential
Good for storage

Question 22

How do you do the iodine test for starch?

Answer 22

Add iodine dissolved in potassium iodide solution to sample.

Pos= browny-orange to blue-black colour change.

Question 23

What’s glycogen the main energy storage material in?

Answer 23

Animals.

Question 24

How do animals store excess glucose?

Answer 24

As glycogen (another polysaccharide of alpha glucose)

Question 25

What’s the structure of glycogen?

Answer 25

Similar to amylopectin but more side branches.

Question 26

Why is amylopectins structure important for energy release in animals?

Answer 26

Lots of branches means stored glucose can be released quickly.

Question 27

Why is amylopectin good for storage?

Answer 27

Compact.

Question 28

What is cellulose a major component in?

Answer 28

Plant cell walls.

Question 29

What’s cellulose’s structure?

Answer 29

Long, unbranched chains of beta-glucose.

Straight cellulose chains.

Question 30

Bonds that link cellulose chains?

Answer 30

Hydrogen

Question 31

What are the storm fibres formed when cellulose chains link?

Answer 31

Microfibrils.