Carbohydrates

Question 1

What do Carbohydrates Contain?

Answer 1

Carbohydrates contain carbon, hydrogen, and oxygen

Question 2

What is the ratio of hydrogen atoms to oxygen atoms?

Answer 2

There are twice as many hydrogen atoms as oxygen atoms (the same as water)

Question 3

What are the three types of carbohydrates?

Answer 3

Monosaccharides
Disaccharides
Polysaccharides

Question 4

What are monosaccharides?

Answer 4

Monosaccharides are single sugars. Different monosaccharides contain different numbers of carbon atoms.

Question 5

What are Disaccharides?

Answer 5

Disaccharides are carbohydrates that contain two monosaccharides joined together by a glycosidic bond during a condensation reaction.

Question 6

What are polysaccharides?

Answer 6

Polysaccharides are large molecules that contain many monosaccharides

Question 7

Name some monosaccharides:

Answer 7

Glucose
Fructose
Galactose

Question 8

Name some disaccharides:

Answer 8

Sucrose
Lactose
Maltose

Question 9

Name some polysaccharides:

Answer 9

Storage - Starch and glycogen

Structure - Cellulose and chitin

Question 10

What is glucose’s formula?

Answer 10

C6H12O6

Question 11

What are the two isomers of glucose?

Answer 11

Alpha (DDUDU)

Beta (UDUDU)

Question 12

What is maltose made up of?

Answer 12

Two alpha glucose joined by a glycosidic bond - The two OHs on the bottom change to an oxygen

Question 13

What is sucrose formed by?

Answer 13

Alpha glucose and fructose

Question 14

What is the test for sugars?

Answer 14

Benedict’s solution - starts as light blue and goes orange if simple sugars are present.

Question 15

What is a reduction?

Answer 15

A reduction is gain of electrons or hydrogen

Question 16

What is a glycosidic bond?

Answer 16

A glycosidic bond is a chemical bond formed as a result of condensation between two monosaccharides

Question 17

What is amylose made of?

Answer 17

Long chains of alpha glucose

Question 18

What is starch?

Answer 18

A substance found in plants that makes up for the most important fuels in the human diet. It is present in 30% of what we eat and is a mixture of amylose and amylopectin.

Question 19

How do you test for starch?

Answer 19

A drop of iodine solution will turn blue/black if starch is present

Question 20

What is starch used for in plants?

Answer 20

Starch in plants is used for storage in seeds and in short term such as overnight when photosynthesis cannot occur.

Question 21

Why is starch good for storage in plants?

Answer 21

Starch is insoluble and does not easily diffuse out of cells or affect water potential or osmosis. It can easily be broken down by enzymes that plants have.

Question 22

How do animals/humans break down starch?

Answer 22

Humans have a digestive enzyme called amylase that hydrolyses starch to maltose which is then hydrolysed to glucose.

Question 23

Where is glycogen stored?

Answer 23

It is stored in the liver where it is slowly released to maintain blood glucose concentration

Question 24

What are the two types of glycosidic bonds?

Answer 24

1,4 and 1,6

Question 25

What is the purpose of cellulose?

Answer 25

The purpose of cellulose is the strength of the plant cell wall. Cellulose is a polysaccharide and a polymer of glucose. The monomer in cellulose is beta glucose. The glucose in cellulose are beta so the oxygen bond alternates top to bottom

Question 26

Why is cellulose good?

Answer 26

It can stretch due to its structure but is also strong enough to support the plant