Glycosidic Bond

Question 1

How are disaccharides and polysaccharides formed?

Answer 1

• 2 Hydroxyl groups on different saccharides
• Covalently bond
• Condensation reaction
• Glycosidic bond
• Oxygen links 2 molecules
• Catalysed by enzymes specific to which OH groups are reacting

Question 2

Types of glycosidic bonds between :

Maltose
Sucrose
Cellulose
Amylose
Amylopectin

Answer 2

Maltose - α 1,4
Sucrose - α 1, 2
Cellulose - β 1, 4
Amylose - α 1, 4
Amylopectin - α 1, 4 and 1, 6

Question 3

How is the glycosidic bond broken? Examples?

Answer 3

• Hydrolysis
• Catalysed by enzymes
• Digesting food, breakdown of stored carbs in muscle and liver cells for cellular respiration

Question 4

How to get a positive benidicts test from sucrose

Answer 4

• Heated with HCL
• Water hydrolyses glycosidic bond
• 2 monosaccharides test positive in benedict’s test