Monosaccharides

Question 1

What is a feature of monosaccharides and why?

Answer 1

Soluble in water - lots of hydroxyl (OH) groups so hydrophilic

Question 2

What are pentose and hexose sugars and which is glucose and which is ribose?

Answer 2

Pentose - 5 carbon atoms (ribose)
Hexose - 6 carbons (glucose)

Question 3

What is the difference between alpha and beta glucose?

Answer 3

Alpha glucose - Carbon 1 hydroxyl group below the ring
Beta glucose - Carbon 1 hydroxyl group above the ring

Question 4

How does a disaccharide form and when else is formed?

Answer 4

Two monosaccharides chemically reacting together.
A molecule of water is also released, formed by a hydrogen atom from one monosaccharide and a hydroxyl group from another
This is a condensation reaction

Question 5

What are the 3 disaccharides and which monosaccharides react to form them?

Answer 5

Maltose (glucose + glucose)
Sucrose (glucose + fructose)
Lactose (glucose + galactose)

Question 6

What type of bond is formed in a disaccharide?

Answer 6

Glycosidic bond

Question 7

How do you break a glycosidic bond and what reaction is this?

Answer 7

Add water. This a hydrolysis reaction

Question 8

How do you break a Glycosidic bond and what reaction is this?

Answer 8

Add water. This a hydrolysis reaction

Question 9

Why is glucose soluble in water?

Answer 9

It contains a large number of hydroxyl groups