311 312 Mono/Polymers And Carbohydrates

Question 1

What is a monomer? (4)
Give some examples

Answer 1

Smaller units that form together to make larger units.

• Monosaccharides (glucose, fructose, galactose)
• Amino acids
• Nucleotides

Question 2

What is a polymer?
Give some examples (4)

Answer 2

Molecules formed when many monomers joined together

• Polysaccharides
• Proteins
• DNA/RNA

Question 3

What happens in a condensation reaction? (1)

Answer 3

A chemical bond is formed between two molecules and a water molecule is produced.

Question 4

What happens in a hydrolysis reaction (1)

Answer 4

A water molecule used to break a chemical bond between two molecules

Question 5

Name 3 monosaccharides (3)

Answer 5

• Glucose
• Fructose
• Galactose

Question 6

Name the type of bond when monosaccharides react (2)

Answer 6

(1,4) (1,6) Glycosidic bond

Question 7

Name three disaccharides and their respective 2 monosaccharides. (3)

Answer 7

• Maltose (α-glucose + α-glucose)
• Sucrose (α-glucose + fructose)
• Lactose (α-glucose + galactose)

Question 8

What is an isomer? (2)

Answer 8

Molecules where the molecular formula stays the same, but the structural formula is different.

Question 9

What is the difference between a-glucose and b-glucose? (3)

Answer 9

OH group on Carbon-1
For a-glucose it’s below
For b-glucose it is above

Question 10

What are the three storage polysaccharides? (3)

Answer 10

• Glycogen
• Amylose
• Amylopectin

Question 11

What is the structure of Glycogen? (2)

Answer 11

• Heavily branched
• Linked with 1,4 glycosidic bonds
• Branched with 1,6 glycosidic bonds

Question 12

How does the structure of Glycogen relate to its function? (3)

Answer 12

• Insoluble - does not diffuse out of cells, does not affect water potential
• Compact - can be stored in small places
• Highly branched - rapid and efficient access to glucose when energy needed

Question 13

What is the structure of Starch? (2)

Answer 13

• Lightly branched
• Linked with 1,4 glycosidic bonds, branched with 1,6 glycosidic bonds

Question 14

How does the structure of Starch relate to its function?

Answer 14

• Insoluble - doesn’t affect water potential
• Large - doesn’t diffuse out of cells
• Compact (helical structure) - stored in small places
• Branched - rapid and efficient access to glucose when energy needed

Question 15

What is the structure of Cellulose? How is it arranged?

Answer 15

• Straight chains of b-glucose
• 1,4 glycosidic bond

Arranged by alternative b-glucose molecules turned upside down

Question 16

How does the structure of Cellulose relate to its function?

Answer 16

Long, straight chains of b-glucose run parallel to each other and are cross-linked with Hydrogen bonds which add collective strength, and they are grouped to form microfibrils, which are grouped to form fibres.