monomers and polymers

Question 1

Define monomer

Answer 1

Small, single units which can bond together to form a polymer

Question 2

Define polymer

Answer 2

A macromolecule made up of similar/identical monomers bonded together via condensation reactions

Question 3

Give 3 examples of monosaccharides

Answer 3

• glucose
• galactose
• fructose

Question 4

What are monosaccharides?

Answer 4

The monomers from which larger carbohydrates are made

Question 5

What are hexoses?

Answer 5

6 Cs

Question 6

Name 2 Pentose sugars

Answer 6

• ribose
• deoxyribose

Question 7

What are the two isomers of glucose?

Answer 7

• Alpha glucose
• beta glucose

Question 8

What are disaccharides?

Answer 8

Two monosaccharides joined by a glycosidic bond via a condensation reaction

Question 9

give 3 examples of disaccharides

Answer 9

• maltose (glucose + glucose)
• sucrose (glucose + fructose)
• galactose (glucose + galactose)

Question 10

what is a polysaccharide made up from?

Answer 10

made up of lots of monosaccharides joined together with glycosidic bonds via condensation reactions

Question 11

give some properties of polysaccharides

Answer 11

• insoluble
• compact
• used for long term energy storage, can be broken down easily to give glucose for respiration
• can be used for construction (cellulose in cell walls)

Question 12

what types of glucose is starch, glycogen and cellulose made from?

Answer 12

starch: made from alpha glucose
glycogen: made from alpha glucose
cellulose: made from beta glucose

Question 13

what are the 3 types of glycosidic bonds you can have?

Answer 13

a-1,4 glycosidic bond: alpha glucose, between OH on C1 and OH group on C4 of another carbon
a-1,6 glycosidic bond: alpha glucose, between OH on C1 and OH on C6 of another carbon
B-1,4 glycosidic bond: Beta glucose, between OH on C1 and OH on C4 of another carbon

Question 14

what happens if a molecule has both a-1,4 and a-1,6 bonds?

Answer 14

the molecule will have branched chains

Question 15

what happens if a molecule only has 1,4 bonds present?

Answer 15

the molecule will have straight chains

Question 16

what is starch

Answer 16

• energy storage molecule in plant cells
• starch is a mixture of two polysaccharides made from a-glucose: amylose and amylopectin
• amylose is a chain of many a-glucoses linked by a-1,4 glycosidic bonds
• amylopectin is also a chain of a-glucoses, it has a mixture of a-1,4 and 1,6 glycosidic bonds

Question 17

what properties of starch suit it to energy storage?

Answer 17

• helical/coiled so it is compact
• insoluble so it can be stored in cells without changing the water potential
• large so cannot diffuse out of cells
• amylopectin is branched so rapid release of a-glucose when necessary for respiration

Question 18

what is glycogen?

Answer 18

• glycogen is a polymer of a-glucose
• it has a-1,4 and a-1,6 glycosidic bonds
• it is branched like amylopectin but has shorter chains and more highly branched

Question 19

properties that suit glycogen to energy storage

Answer 19

• compact
• insoluble so can be stored in cells without changing the water potential
• large so cannot diffuse out of cells
• branched so rapid release of a-glucose when necessary for respiration

Question 20

what is cellulose?

Answer 20

• cellulose is not used for energy storage, its a major structural component of cell walls
• formed from B-glucose
• B-1,4 glycosidic bonds

Question 21

what is the arrangement of celluloses chains?

Answer 21

• unbranched straight chains allow the chains to run parallel to each other and form hydrogen bonds between
• chains are then grouped to form microfibrils which are then arranged into parallel groups called fibres

Question 22

what are some properties that suit cellulose as a structural component of plant cell walls

Answer 22

• the structure of cellulose makes it strong and rigid
• b-1,4 glycosidic bonds mean that cellulose forms long, straight unbranched chains
• allows chains to be arranged parallel and form H bonds (adding strength)
• forming microfibrils