Carbohydrates 2

Question 1

What is a monomer carbohydrate called?

Answer 1

A monosaccharide

Question 2

What is a dimer carbohydrate called?

Answer 2

Disaccharide

Question 3

What is a polymer carbohydrate called?

Answer 3

Polysaccharide

Question 4

What is an isomer?

Answer 4

Molecule of the same subunits and chemical formula but a different formation of the atoms

Question 5

Give three examples of Disaccharides

Answer 5

Lactose sucrose, maltose

Question 6

What is lactose?

Answer 6

Glucose and galactose

Question 7

What is sucrose?

Answer 7

Glucose and fructose

Question 8

What is maltose?

Answer 8

Glucose and glucose

Question 9

Give three examples of polysaccharides

Answer 9

Starch, glycogen, cellulose and chitin (not a true polysaccharide as it includes nitrogen in it’s functional group of acetyl amide)

Question 10

What three elements are carbohydrates made up of?

Answer 10

Carbon hydrogen oxygen

Question 11

Give a brief description of what starch does

Answer 11

Storage of glucose in plants

Question 12

Give a brief description of what glycogen does

Answer 12

Storage of glucose in liver and muscles

Question 13

Give a brief description of what cellulose does

Answer 13

Makes up cell walls

Question 14

Give a brief description of what chitin does

Answer 14

Makes up the exoskeleton of insects and the cell wall of fungi

Question 15

What categories of monosaccharides are there?

Answer 15

Triose pentose, hexose

Ose usually means said molecule is a carbohydrate

Question 16

What is the equation for monosaccharides?

Answer 16

(C(H20))n

Question 17

What is hexose and what are examples of it?

Answer 17

A monosaccharide with six carbon atoms. Glucose fructose, galactose
Always C6H12O6
Learn to draw glucose, recognise fructose and galactose (see booklet)

Question 18

What is pentose and what are examples of it?

Answer 18

A monosaccharide with 5 carbon atoms.
Always C5H10O5
Deoxyribose in DNA and ribose in RNA

Question 19

What is triose and what are examples of it?

Answer 19

A monosaccharide with 3 carbon atoms.
Always C3H6O3
Glyceraldehyde - part of cellular respiration

Question 20

How many isomers are there of glucose? What are they? What is the difference between them?

Answer 20

2 and they are called alpha and beta glucose. Alpha glucose has the OH below carbon 1, where is beta glucose has it above carbon 1. Learn how to draw both of them

Question 21

Are monosaccharides always in a ring structure?

Answer 21

No, all of the types of monosaccharides can be in a straight carbon chain. Have a look at the booklet

Question 22

What is the basic function of glycogen?

Answer 22

the main storage product in animals

Question 23

What bonds does glycogen have ?

Answer 23

(alpha symbol)-1,4-glycosidic bonds and (alpha symbol)-1,6-glycosidic bonds

Question 24

Where is glycogen found?

Answer 24

Liver cells

Question 25

What is chitin?

Answer 25

Chitin is the same as cellulose and is used in exoskeletons in insects and cells walls in fungi. However, an oh group on each beta glucose is replaced by a nitrogen containing acetyl amide group. This forms a mucopolysaccharide. It means chitin is also waterproof and lightweight. Because the acetyl group alternates position due to the 180 degree rotation it is a heterosaccharide.

Question 26

What shape does glycogen make?

Answer 26

Glycogen is similar to amylopectin but much more branched. The 1-4 glycosidic bond from the straight chain which coils

Question 27

Why is it good for a glucose polysaccharide to be branched?

Answer 27

Because it makes it easier for enzymes to either condense or hydrolyse the glucose.

Question 28

What monomers is cellulose made up of?

Answer 28

Beta glucose

Question 29

Is cellulose soluble and how does it respond to water another solute?

Answer 29

Cellulose is insoluble but is freely permeable to water and other solute

Question 30

What is it that makes starch and glycogen be able to coil?

Answer 30

The glycosidic bonds are on the same side of the molecules as in they all go up or they all go down, not alternating like in cellulose. This means that they can coil, whereas cellulose has the bonds not all on the same side and is therefore non-compactable.

Question 31

What shape does cellulose form?

Answer 31

Cellulose microfibrils, each bonded by hydrogen bonds, form one big macrofibril that in turn joins others to create a cellulose fibre.

Question 32

Describe the structure of a cellulose microfibril.

Answer 32

Adjacent beta glucose molecules rotate 180 degrees allowing 1-4 glycosidic linkages to form. These Bonds form to to produce long straight chains that have a high tensile strength and are non compactable. Adjacent chains then cross-link with each other using hydrogen bonds to form the complete microfibrils. This creates the strength.

Question 33

What is a function of cellulose?

Answer 33

It is a main constituent of the cell wall in plant cells