Unit 2: Chapter 7 - Proteins

Question 1

What are proteins?

Answer 1

Proteins are the major structural materials of animal tissue and are also involved in the maintenance and regulation of life processes.

Question 2

Could we survive without proteins?

Answer 2

NO

Question 3

What are enzymes under the heading proteins?

Answer 3

Enzymes are proteins which act as biological catalysts.

Question 4

What do proteins contribute to in our body?

Answer 4

Proteins contribute to the growth and repair of our bodies.

Question 5

Which types of foods contain proteins?

Answer 5

Meat, cheese, fish and eggs.

Question 6

Which foods contain a wide range of proteins?

Answer 6

Meat like pork, lamb, beef etc.

Question 7

What happens when we take a protein and heat it with soda lime and what does this show?

Answer 7

When we take a protein and heat it with soda lime we get a pungent alkaline smell given off. The gases are all amines or ammonia. This suggests that the proteins contain nitrogen and this confirms that all plants need nitrogen to manufacture proteins.

Question 8

What is an accurate way of showing what proteins are made of?

Answer 8

By hydrolysing the protein in dilute hydrochloric acid for several hours.

Question 9

What are proteins made of?

Answer 9

Amino acids.

Question 10

What are amino acids and what are they made of?

Answer 10

Amino acids, the building blocks from which proteins are formed, are relatively small molecules which all contain an amine group, —NH2, and a carboxyl group, —COOH.

Question 11

What are the two functional groups in amino acids?

Answer 11

The amine group - NH2, and the carboxyl group - COOH.

Question 12

What is a process to determine what amino acids are present in a protein?

Answer 12

Chromatography

Question 13

What does the condensation of amino acids require?

Answer 13

Acids to join together.

Question 14

What is the link called from the condensation reaction of amino acids?

Answer 14

The amide link.

Question 15

What does an amide link look like?

Answer 15

[
 H - N
        [                 Can look in data book
O = C
        [

Question 16

When circling an amide link what have you always got leave?

Answer 16

Empty bonds at the carbon and the nitrogen.

Question 17

What are proteins made of and what does this reaction produce?

Answer 17

Proteins are made of many amino acid molecules linked together by condensation reactions. In these reactions, the amino group of one amino acid and the carboxyl group of another amino acid join, with the elimination of water.

Question 18

What is the link that forms between amino acids known as?

Answer 18

The link which forms between two amino acids is known as a peptide link, —CONH—, or also as an amide link.

Question 19

What are proteins which fulfil different roles in the body formed by linking together?

Answer 19

Proteins which fulfil different roles in the body are formed by linking together differing sequences of amino acids.

Question 20

How are amino acids that the body cannot make obtained by and what are they called?

Answer 20

The amino acids are obtained from the diet and are called essential amino acids.

Question 21

During digestion what produces amino acids?

Answer 21

During digestion, enzyme hydrolysis of protein produces amino acids.

Question 22

What happens during the hydrolysis of a protein

Answer 22

During the hydrolysis of a protein the amide link is broken and a water molecule is inserted.

Question 23

How many different amino acids are there?

Answer 23

20

Question 24

What makes amino acids different?

Answer 24

The alkyl chain they posses.