3.1 Monomers and polymers and Carbohydrates

Question 1

What is a condensation reaction ?

Answer 1

Joining together of two molecules forming a glycosidic bond with the elimination of a water molecule

Question 2

What is a hydrolysis reaction ?

Answer 2

Splitting of two molecules by breaking of a glycosidic bond with the addition of a water molecule

Question 3

What two monomers form the disaccharide, Maltose ?

Answer 3

Glucose + Glucose = Maltose + water

Question 4

What two monomers form the disaccharide, Sucrose ?

Answer 4

Glucose + Fructose = Sucrose + water

Question 5

What two monomers form the disaccharide, Lactose ?

Answer 5

Glucose + Galactose = Lactose + water

Question 6

Explain why benedicts reagent turns red when heated with a reducing sugar

Answer 6

As the sugar donates electrons that reduce blue copper-2 sulfate to orange copper-1 oxide

Question 7

Non reducing sugars do not change the colour of Benedicts reagent. What must you do to the sample for it to be detected ?

Answer 7

Sample must be aqueous- ground up in water if not already a liquid (must hydrolyse to break chemical bonds)

Question 8

What is the structure of ATP

Answer 8

Adenine, Ribose (pentose sugar), 3X phosphate ions

Question 9

ATP is sometimes referred to as an immediate energy source. Explain why

Answer 9

As ATP releases its energy in a single step process and its energy is transferred directly to the reaction requiring it

Question 10

What its a monomer ?

Answer 10

Small units that can join together to form polymers

Question 11

What is a polymer ?

Answer 11

Lots of monomers bonded together

Question 12

Draw a molecule of alpha glucose

Answer 12

H on top, OH on bond underneath

Question 13

Where is the OH bond located on a beta glucose ?

Answer 13

OH on top, H underneath

Question 14

What is a disaccharide ?

Answer 14

Two monosaccharides joined together by a glycosidic bond via a condensation reaction

Question 15

What type of glucose is starch made from ?

Answer 15

Alpha glucose

Question 16

Is starch found in plants or animals ?

Answer 16

In plants

Question 17

What is the function of starch ?

Answer 17

It is a store of glucose

Question 18

What do 1-4 glycosidic bonds create in reference to shape of molecule ?

Answer 18

Unbranched straight chain

Question 19

What do 1-6 glycosidic bonds create in reference to shape of molecule ?

Answer 19

A branched molecule

Question 20

What type of glucose is cellulose made from ?

Answer 20

Beta glucose

Question 21

Where is cellulose found in plants and what is its job ?

Answer 21

It is found in the cell wall and provides structure and strength

Question 22

What type of bonds are found in cellulose ?

Answer 22

1-4 glycosidic bonds

Question 23

What type of bonds are found in starch ?

Answer 23

1-4 glycosidic bond in amylose and 1-4 and 1-6 in amylopectin

Question 24

What type of glucose is glycogen made from?

Answer 24

Alpha glucose

Question 25

Is glycogen found in plants or animals ?

Answer 25

Animals and is located in muscle and liver cells

Question 26

What type of bonds are found in glycogen ?

Answer 26

1-4 and 1-6 glycosidic bonds

Question 27

What is the structure of starch ?

Answer 27

It is made two polymers, Amylose and Amylopectin. Amylose is an unbranched helix which can be compacted to fit a lot of glucose into a small space. Amylopectin is a branched molecule which increases surface area for rapid hydrolysis back to glucose. It is also insoluble so won’t affect water potential.

Question 28

Where are amylose and amylopectin found ?

Answer 28

They are the two polymers that make up starch

Question 29

What is the structure of cellulose ?

Answer 29

It has many hydrogen bonds that provide collective strength. It is also insoluble so will not affect water potential

Question 30

What is the structure of glycogen ?

Answer 30

It has a branched structure which increases surface area for rapid hydrolysis back into glucose. It is also insoluble so will not affect water potential