Carbohydrates

Question 1

What is the general formula for carbs?

Answer 1

(CH20)x

Question 2

What is a monosaccharide and what are some examples?

Answer 2

Monomers from which larger carbs are formed.
Glucose, galactose and fructose.

Question 3

What is the difference between an alpha and beta glucose?

Answer 3

Alpha glucose has the carbon 1 hydroxyl (OH) below the carbon ring. Opposite for beta (above)

Question 4

Why is glucose soluble in water?

Answer 4

Polar hydroxyl groups form H bonds with water

Question 5

What are hexose monosaccarides and give 3 examples

Answer 5

Sugars with 6 carbons. Glucose, fructose, galactose

Question 6

What is a molecule that is soluble in water called?

Answer 6

Hydrophilic

Question 7

What are pentose monosaccarides and give 2 examples

Answer 7

Sugars with 5 carbons. Deoxyribose, ribose

Question 8

What is formed when two alpha glucose molecueles react?

Answer 8

A maltose dissacaride and water

Question 9

What is a condensation reaction?

Answer 9

When two small molecules join to form a larger molecule by removing a functional group that form a small molecule, which is often water

Question 10

What is a glycosidic bond?

Answer 10

The covalent bond joining two monosaccarides together. Forms an oxygen bridge

Question 11

What are the three disaccarides and what are they made from?

Answer 11

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

Question 12

What happens when water is added to a disccaride, and what type of reaction is this?

Answer 12

It breaks the glycosidic bond. A hydrolysis reaction

Question 13

What is the main role of starch and what polysaccarides is it made up of?

Answer 13

Energy storage in plants.
Amylose and amylopectin

Question 14

What are some properties of amylose?

Answer 14

Angle of 1-4 glycosidic bonds causes a helix shape
Compact
Insolube

Question 15

Why is amylose and amylopectin being large polymers an advantage for starch?

Answer 15

They are too large to diffuse out the cell membrane and out of the cell

Question 16

What is the advantage of amylopectin having lots of branches?

Answer 16

It means it has a large number of ends, so the enzymes can break down starch rapidly

Question 17

What are the similarities and differences between amylopectin and glycogen?

Answer 17

Similarities - Branches caused by 1-6 glycosidic bond, compact, insoluble
Differences - Glycogen is in animals and fungi, amylopectin in plants
Glycogen has more branches (so more ends so can be broken down quicker and can release glucose quicker)
Glycogen can store more energy in smaller spaces