1.1 Carbohydrates

Question 1

What is the difference between polysaccharides , monosaccharides and disaccharides

Answer 1

Monosaccharide - A single carbohydrate monomer
- Disaccharide - 2 carbohydrate monomers joined together
Polysaccharide - More than two carbohydrate molecules joined together

Question 2

What examples of monosaccharides

Answer 2

• Glucose
• Fructose
• Galactose

Question 3

What bonds are between disaccharides

Answer 3

• Glycosidic bonds

Question 4

What reaction joins a disaccharide

Answer 4

• Condensation reaction

Question 5

What are the three examples of disaccharides

Answer 5

• Maltose
• Sucrose
• Lactose

Question 6

How does the structure of starch ( amylose relate to its function

Answer 6

AMYLOSE

• Alpha glucose monomers
• 1,4 glycosidic bonds ( long straight chains)
• Unbranched helix
• Coiled
• Insoluble

Function
- Due to it being an unbranched helix, it can compact to fit a lot of glucose in a small space
- Insoluble, doesnt affect water potential
- Carbohydrate store in plants

Question 7

Where is amylose found ?

Answer 7

Plant cells and storage organs

Question 8

Describe the structure of amylopectin

Answer 8

• Alpha glucose monomers
• Contains 1,4 and 1,6 glycosidic bonds ]
• Uncoiled to form more compact globular molecules
• Branched
• Insoluble
• Can be broken down more rapidly

Found in plant cells and storage organs

Question 9

Describe the structure of glycogen and how it relates to its function

Answer 9

• Contains alpha glucose monomers
• Bonded by 1,4 and 1,6 glycosidic bonds
• Large number of side branches so it can be hydrolysed and energy can be released quickly
• Insoluble in water
• Is a large but compact molecule therefore maximising the amount of energy it can store

Question 10

What is cellulose

Answer 10

• Component of plant cell walls

Question 11

Describe the structure of cellulose and how it relates to its function

Answer 11

• Made up of beta helix monomers
• Joined by 1,4 glycosidic bonds
• Un coiled to make microfibrils and strong chains
• Branched
• Insoluble
• found in cell walls

Question 12

Explain in two ways how amylose and glycogen are suitable for energy storage

Answer 12

1 - Can be hydrolysed to release glucose
2- They are compact so large number of glucose molecules can fit into a small volume

Question 13

Why is the dipole nature of water essential for living organisms ?

Answer 13

• Water forms hydrogen bonds between them
• Cohesion and adhesion theory allows water to move against the force of gravity