Carbohydrates

Question 1

What is the general formula of a carbohydrate?

Answer 1

C(H2O)n

Question 2

What are the names for sugars with 3, 5 and 6 carbons?

Answer 2

Triose, pentose, hexose

Question 3

Name three hexose monosaccharides

Answer 3

Fructose, galactose, glucose

Question 4

Which monosaccharides make up the disaccharides sucrose, lactose and maltose?

Answer 4

Sucrose=glucose and fructose, lactose=glucose and galactose, maltose= glucose and glucose

Question 5

Describe the difference between alpha and beta glucose

Answer 5

On alpha the OH group on carbon 1 is below the ring, on beta it is above

Question 6

Which reaction joins two monosaccharides and what bond is formed?

Answer 6

Condensation, glycosidic

Question 7

Which reaction breaks the bond in a disaccharide?

Answer 7

Hydrolysis

Question 8

Describe the structure of starch

Answer 8

a polymer of alpha glucose. Composed of coiled-chain amylose containing 1-4 glycosidic bonds and branched amylopectin containing 1-4 and 1-6 glycosidic bonds

Question 9

Describe the structure of glycogen

Answer 9

a polymer of alpha glucose- branched structure containing 1-4 and 1-6 glycosidic bonds

Question 10

Describe the structure of cellulose

Answer 10

a polymer of beta glucose, straight chains with 1-4 glycosidic bonds, every other glucose rotated 180 degrees. H bonds holding together chains to form microfibrils, making it strong

Question 11

Describe the structure of chitin

Answer 11

a polymer of beta glucose with acetylamine groups, straight chains with 1-4 glycosidic bonds, every other glucose rotated 180 degrees. H bonds holding together chains to form microfibrils, making it strong

Question 12

Give three reasons starch and glycogen are good storage molecules

Answer 12

Glucose can be added and removed easily, they are compact and they have no osmotic effect because they are insoluble